diff --git a/web/app/appointments/page.js b/web/app/appointments/page.js
index bec8bd78..fac5a86f 100644
--- a/web/app/appointments/page.js
+++ b/web/app/appointments/page.js
@@ -226,10 +226,11 @@ function AppointmentsPage() {
 
   useEffect(() => {
     if (!authLoading && !user) {
-      router.push("/login");
+      const target = preselectedPetId ? `/appointments?petId=${encodeURIComponent(preselectedPetId)}` : "/appointments";
+      router.push(`/login?next=${encodeURIComponent(target)}`);
     }
 
-  }, [authLoading, user, router]);
+  }, [authLoading, user, router, preselectedPetId]);
 
   useEffect(() => {
     if (!token) {
diff --git a/web/app/globals.css b/web/app/globals.css
index da8ce03b..8571bfeb 100644
--- a/web/app/globals.css
+++ b/web/app/globals.css
@@ -1076,6 +1076,13 @@ body {
   align-items: center;
   justify-content: center;
   margin-bottom: 0.25rem;
+  overflow: hidden;
+}
+
+.profile-avatar-image {
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
 }
 
 .profile-name {
@@ -1105,6 +1112,37 @@ body {
   padding-top: 1rem;
 }
 
+.profile-update-form {
+  width: 100%;
+  display: grid;
+  gap: 0.9rem;
+}
+
+.profile-update-title {
+  margin: 0.25rem 0 0;
+  font-size: 1.1rem;
+  color: #222;
+}
+
+.profile-avatar-actions {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 0.75rem;
+}
+
+.profile-avatar-upload-btn {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  padding: 0.65rem 1rem;
+  border-radius: 8px;
+  background: #fff3e0;
+  color: #a65c00;
+  font-weight: 600;
+  cursor: pointer;
+}
+
 .profile-field-row {
   display: flex;
   justify-content: space-between;
diff --git a/web/app/login/page.js b/web/app/login/page.js
index dcc78d02..2e7d1fe1 100644
--- a/web/app/login/page.js
+++ b/web/app/login/page.js
@@ -1,13 +1,25 @@
 "use client";
 
+import dynamic from "next/dynamic";
 import Link from "next/link";
 import { useState } from "react";
-import { useRouter } from "next/navigation";
+import { useRouter, useSearchParams } from "next/navigation";
 import { useAuth } from "@/context/AuthContext";
 
-export default function LoginPage() {
+function resolveNextPath(candidate) {
+  if (!candidate || !candidate.startsWith("/")) {
+    return "/";
+  }
+  if (candidate.startsWith("//") || candidate.startsWith("/login") || candidate.startsWith("/register")) {
+    return "/";
+  }
+  return candidate;
+}
+
+function LoginPage() {
   const {login} = useAuth();
   const router = useRouter();
+  const searchParams = useSearchParams();
 
   const [username, setUsername] = useState("");
   const [password, setPassword] = useState("");
@@ -21,7 +33,7 @@ export default function LoginPage() {
 
     try {
       await login(username, password);
-      router.push("/");
+      router.push(resolveNextPath(searchParams.get("next")));
     } 
     
     catch (err) {
@@ -68,9 +80,13 @@ export default function LoginPage() {
         
         <p className="auth-switch">
           Don&apos;t have an account?{" "}
-          <Link href="/register" className="auth-switch-link">Register here</Link>
+          <Link href={searchParams.get("next") ? `/register?next=${encodeURIComponent(searchParams.get("next"))}` : "/register"} className="auth-switch-link">Register here</Link>
         </p>
       </div>
     </main>
   );
 }
+
+export default dynamic(() => Promise.resolve(LoginPage), {
+  ssr: false,
+});
diff --git a/web/app/profile/page.js b/web/app/profile/page.js
index 6b28aa35..d0b78c5e 100644
--- a/web/app/profile/page.js
+++ b/web/app/profile/page.js
@@ -7,7 +7,7 @@ import { useAuth } from "@/context/AuthContext";
 const API_BASE = "";
 
 export default function ProfilePage() {
-  const {user, token, loading, logout} = useAuth();
+  const {user, token, loading, logout, refreshUser} = useAuth();
   const router = useRouter();
 
   const [pets, setPets] = useState([]);
@@ -19,14 +19,27 @@ export default function ProfilePage() {
   const [breed, setBreed] = useState("");
   const [submitting, setSubmitting] = useState(false);
   const [petError, setPetError] = useState(null);
+  const [profileForm, setProfileForm] = useState({ fullName: "", email: "", phone: "" });
+  const [profileSubmitting, setProfileSubmitting] = useState(false);
+  const [profileError, setProfileError] = useState(null);
+  const [profileSuccess, setProfileSuccess] = useState(null);
+  const [avatarSubmitting, setAvatarSubmitting] = useState(false);
 
   useEffect(() => {
     if (!loading && !user) {
-      router.replace("/login");
+      router.replace(`/login?next=${encodeURIComponent("/profile")}`);
     }
 
   }, [user, loading, router]);
 
+  useEffect(() => {
+    setProfileForm({
+      fullName: user?.fullName || "",
+      email: user?.email || "",
+      phone: user?.phone || "",
+    });
+  }, [user]);
+
   const loadPets = useCallback(() => {
     if (!token) return;
     setLoadingPets(true);
@@ -50,6 +63,105 @@ export default function ProfilePage() {
     router.push("/");
   }
 
+  async function handleProfileSubmit(e) {
+    e.preventDefault();
+    setProfileSubmitting(true);
+    setProfileError(null);
+    setProfileSuccess(null);
+
+    try {
+      const res = await fetch(`${API_BASE}/api/v1/auth/me`, {
+        method: "PUT",
+        headers: {
+          "Content-Type": "application/json",
+          Authorization: `Bearer ${token}`,
+        },
+        body: JSON.stringify(profileForm),
+      });
+
+      const data = await res.json().catch(() => null);
+      if (!res.ok) {
+        throw new Error(data?.message || `Request failed (${res.status})`);
+      }
+
+      await refreshUser();
+      setProfileSuccess("Profile updated successfully.");
+    }
+
+    catch (err) {
+      setProfileError(err.message);
+    }
+
+    finally {
+      setProfileSubmitting(false);
+    }
+  }
+
+  async function handleAvatarUpload(file) {
+    if (!file) {
+      return;
+    }
+
+    const formData = new FormData();
+    formData.append("avatar", file);
+    setAvatarSubmitting(true);
+    setProfileError(null);
+    setProfileSuccess(null);
+
+    try {
+      const res = await fetch(`${API_BASE}/api/v1/auth/me/avatar`, {
+        method: "POST",
+        headers: { Authorization: `Bearer ${token}` },
+        body: formData,
+      });
+
+      const data = await res.json().catch(() => null);
+      if (!res.ok) {
+        throw new Error(data?.message || "Failed to upload avatar");
+      }
+
+      await refreshUser();
+      setProfileSuccess(data?.message || "Avatar updated successfully.");
+    }
+
+    catch (err) {
+      setProfileError(err.message);
+    }
+
+    finally {
+      setAvatarSubmitting(false);
+    }
+  }
+
+  async function handleAvatarDelete() {
+    setAvatarSubmitting(true);
+    setProfileError(null);
+    setProfileSuccess(null);
+
+    try {
+      const res = await fetch(`${API_BASE}/api/v1/auth/me/avatar`, {
+        method: "DELETE",
+        headers: { Authorization: `Bearer ${token}` },
+      });
+
+      const data = await res.json().catch(() => null);
+      if (!res.ok) {
+        throw new Error(data?.message || "Failed to delete avatar");
+      }
+
+      await refreshUser();
+      setProfileSuccess(data?.message || "Avatar removed successfully.");
+    }
+
+    catch (err) {
+      setProfileError(err.message);
+    }
+
+    finally {
+      setAvatarSubmitting(false);
+    }
+  }
+
   function openAddForm() {
     setEditingPet(null);
     setPetName("");
@@ -170,7 +282,11 @@ export default function ProfilePage() {
     <main className="profile-page-layout">
       <div className="profile-card">
         <div className="profile-avatar-circle">
-          {(user.fullName || user.username).charAt(0).toUpperCase()}
+          {user.avatarUrl ? (
+            <img src={user.avatarUrl} alt={user.fullName || user.username} className="profile-avatar-image" />
+          ) : (
+            (user.fullName || user.username).charAt(0).toUpperCase()
+          )}
         </div>
 
         <h1 className="profile-name">{user.fullName || user.username}</h1>
@@ -185,7 +301,65 @@ export default function ProfilePage() {
           ))}
         </dl>
 
-        <button className="auth-submit-btn profile-logout-btn" onClick={handleLogout}>
+        <form className="profile-update-form" onSubmit={handleProfileSubmit}>
+          <h2 className="profile-update-title">Update Profile</h2>
+          {profileError && <div className="appt-error">{profileError}</div>}
+          {profileSuccess && <div className="appt-success">{profileSuccess}</div>}
+          <label className="appt-label">
+            Full Name
+            <input
+              className="appt-input"
+              type="text"
+              value={profileForm.fullName}
+              onChange={(e) => setProfileForm((current) => ({ ...current, fullName: e.target.value }))}
+              maxLength={100}
+            />
+          </label>
+          <label className="appt-label">
+            Email
+            <input
+              className="appt-input"
+              type="email"
+              value={profileForm.email}
+              onChange={(e) => setProfileForm((current) => ({ ...current, email: e.target.value }))}
+              required
+            />
+          </label>
+          <label className="appt-label">
+            Phone
+            <input
+              className="appt-input"
+              type="text"
+              value={profileForm.phone}
+              onChange={(e) => setProfileForm((current) => ({ ...current, phone: e.target.value }))}
+              maxLength={20}
+            />
+          </label>
+          <div className="profile-avatar-actions">
+            <label className="profile-avatar-upload-btn">
+              <input
+                type="file"
+                accept="image/jpeg,image/png,image/gif"
+                className="profile-pet-upload-input"
+                onChange={(e) => {
+                  handleAvatarUpload(e.target.files?.[0] || null);
+                  e.target.value = "";
+                }}
+              />
+              {avatarSubmitting ? "Working..." : user.avatarUrl ? "Change Avatar" : "Upload Avatar"}
+            </label>
+            {user.avatarUrl && (
+              <button type="button" className="profile-pet-delete-btn" onClick={handleAvatarDelete} disabled={avatarSubmitting}>
+                Remove Avatar
+              </button>
+            )}
+          </div>
+          <button type="submit" className="appt-submit-btn" disabled={profileSubmitting || avatarSubmitting}>
+            {profileSubmitting ? "Saving..." : "Save Profile"}
+          </button>
+        </form>
+
+        <button type="button" className="auth-submit-btn profile-logout-btn" onClick={handleLogout}>
           Log Out
         </button>
       </div>
@@ -194,7 +368,7 @@ export default function ProfilePage() {
         <div className="profile-pets-section">
           <div className="profile-pets-header">
             <h2 className="profile-pets-title">My Pets</h2>
-            <button className="profile-pets-add-btn" onClick={openAddForm}>+ Add Pet</button>
+            <button type="button" className="profile-pets-add-btn" onClick={openAddForm}>+ Add Pet</button>
           </div>
 
           {showForm && (
@@ -285,11 +459,11 @@ export default function ProfilePage() {
                     {pet.breed && <span className="profile-pet-card-detail">{pet.breed}</span>}
                   </div>
                   <div className="profile-pet-card-actions">
-                    <button className="profile-pet-edit-btn" onClick={() => openEditForm(pet)}>Edit</button>
-                    <button className="profile-pet-delete-btn" onClick={() => handleDeletePet(pet.customerPetId)}>Remove</button>
-                  </div>
-                </div>
-              ))}
+                     <button type="button" className="profile-pet-edit-btn" onClick={() => openEditForm(pet)}>Edit</button>
+                     <button type="button" className="profile-pet-delete-btn" onClick={() => handleDeletePet(pet.customerPetId)}>Remove</button>
+                   </div>
+                 </div>
+               ))}
             </div>
           )}
         </div>
diff --git a/web/app/register/page.js b/web/app/register/page.js
index eb9de480..17f49672 100644
--- a/web/app/register/page.js
+++ b/web/app/register/page.js
@@ -1,13 +1,25 @@
 "use client";
 
+import dynamic from "next/dynamic";
 import Link from "next/link";
 import { useState } from "react";
-import { useRouter } from "next/navigation";
+import { useRouter, useSearchParams } from "next/navigation";
 import { useAuth } from "@/context/AuthContext";
 
-export default function RegisterPage() {
+function resolveNextPath(candidate) {
+  if (!candidate || !candidate.startsWith("/")) {
+    return "/";
+  }
+  if (candidate.startsWith("//") || candidate.startsWith("/login") || candidate.startsWith("/register")) {
+    return "/";
+  }
+  return candidate;
+}
+
+function RegisterPage() {
   const {register} = useAuth();
   const router = useRouter();
+  const searchParams = useSearchParams();
 
   const [form, setForm] = useState({
     fullName: "",
@@ -41,7 +53,7 @@ export default function RegisterPage() {
         phone: form.phone,
         password: form.password,
       });
-      router.push("/");
+      router.push(resolveNextPath(searchParams.get("next")));
     } 
     
     catch (err) {
@@ -144,9 +156,13 @@ export default function RegisterPage() {
         
         <p className="auth-switch">
           Already have an account?{" "}
-          <Link href="/login" className="auth-switch-link">Log in here</Link>
+          <Link href={searchParams.get("next") ? `/login?next=${encodeURIComponent(searchParams.get("next"))}` : "/login"} className="auth-switch-link">Log in here</Link>
         </p>
       </div>
     </main>
   );
 }
+
+export default dynamic(() => Promise.resolve(RegisterPage), {
+  ssr: false,
+});
diff --git a/web/context/AuthContext.js b/web/context/AuthContext.js
index 5a9b0d08..e861f624 100644
--- a/web/context/AuthContext.js
+++ b/web/context/AuthContext.js
@@ -19,6 +19,28 @@ export function AuthProvider({ children }) {
   const [token, setToken] = useState(null);
   const [loading, setLoading] = useState(true);
 
+  const refreshUser = useCallback(async (providedToken) => {
+    const activeToken = providedToken ?? token;
+    if (!activeToken) {
+      setUser(null);
+      return null;
+    }
+
+    const userInfo = await fetchCurrentUser(activeToken);
+    if (!userInfo) {
+      localStorage.removeItem(TOKEN_KEY);
+      setToken(null);
+      setUser(null);
+      return null;
+    }
+
+    if (!token) {
+      setToken(activeToken);
+    }
+    setUser(userInfo);
+    return userInfo;
+  }, [token]);
+
   useEffect(() => {
     const stored = localStorage.getItem(TOKEN_KEY);
     if (!stored) {
@@ -26,17 +48,14 @@ export function AuthProvider({ children }) {
 
       return;
     }
-    fetchCurrentUser(stored)
-      .then((data) => {
-        if (data) {
-          setToken(stored);
-          setUser(data);
-        } 
-        
-        else {
-          localStorage.removeItem(TOKEN_KEY);
-        }
-      }).catch(() => localStorage.removeItem(TOKEN_KEY)).finally(() => setLoading(false));}, []);
+    refreshUser(stored)
+      .catch(() => {
+        localStorage.removeItem(TOKEN_KEY);
+        setToken(null);
+        setUser(null);
+      })
+      .finally(() => setLoading(false));
+  }, [refreshUser]);
 
   const login = useCallback(async (username, password) => {
     const res = await fetch("/api/v1/auth/login", {
@@ -55,12 +74,10 @@ export function AuthProvider({ children }) {
     localStorage.setItem(TOKEN_KEY, jwt);
     setToken(jwt);
 
-    const userInfo = await fetchCurrentUser(jwt);
-
-    setUser(userInfo);
+    const userInfo = await refreshUser(jwt);
 
     return userInfo;
-  }, []);
+  }, [refreshUser]);
 
   const register = useCallback(async ({ username, password, email, fullName, phone }) => {
     const res = await fetch("/api/v1/auth/register", {
@@ -79,11 +96,10 @@ export function AuthProvider({ children }) {
     localStorage.setItem(TOKEN_KEY, jwt);
     setToken(jwt);
 
-    const userInfo = await fetchCurrentUser(jwt);
-    setUser(userInfo);
+    const userInfo = await refreshUser(jwt);
 
     return userInfo;
-  }, []);
+  }, [refreshUser]);
 
   const logout = useCallback(() => {
     localStorage.removeItem(TOKEN_KEY);
@@ -91,7 +107,7 @@ export function AuthProvider({ children }) {
     setUser(null);}, []);
 
   return (
-    <AuthContext.Provider value={{ user, token, loading, login, logout, register }}>
+    <AuthContext.Provider value={{ user, token, loading, login, logout, register, refreshUser }}>
       {children}
     </AuthContext.Provider>
   );