Admin Panel

<?php
session_start(); 
include "config.php"; 
if($logged[username] && $logged[userlevel] == 6)
{ 
switch($_GET[page]) 
{ 
default: 
$fetch = mysql_query("SELECT * FROM `members` ORDER BY username ASC"); 
while($users = mysql_fetch_array($fetch)) 
{ 
echo ("<a href='?page=edit&username=$users[username]'>- $users[username]</a><br>"); 
}
break;
 
case 'edit': 
 
$user = mysql_query("SELECT * FROM `members` where username = '$_GET[username]'");
$users = mysql_fetch_array($user); 
echo ("
<form method='POST'> 
<table width='100%'> 
<tr> 
<td align='right' width='25%'> 
User Level</td> 
<td align='left'> 
<select name='level'> 
<option value='2'>User</option> 
<option value='4'>Mod</option> 
<option value='6'>Admin</option> 
</select> </td> 
</tr> 
<tr> 
<td align='right' width='25%'> 
Email</td> 
<td align='left'> 
<input type='text' size='25' maxlength='25' name='email' value='$users[email]'></td> 
</tr> 
<tr> 
<td align='right' width='25%'>Location</td> 
<td align='left'> 
<input size='25' name='location' value='$users[location]'></td> 
</tr> 
<tr> 
<td align='right' width='25%'>Age</td> 
<td align='left'> 
<input size='25' name='age'  value='$users[age]'></td> 
</tr> 
<tr> 
<td align='center'></td> 
<td align='left'> 
<input type='hidden' value='$_GET[username]' name='username'>
<input type='submit' name='submit' value='Update'></td> 
</tr> 
</table> 
</form>  
");
if($_POST[submit]) 
{ 
$username = htmlspecialchars($_POST[username]);
$email = htmlspecialchars($_POST[email]);
$age = htmlspecialchars($_POST[age]); 
$location = htmlspecialchars($_POST[location]); 
$level = htmlspecialchars($_POST[level]);
 
$update = mysql_query("UPDATE `members` SET `location` = '$location', `age` = '$age', `level` = '$level', `email` = '$email' WHERE `username` = '$username'"); 
echo ("Thank you $logged[username], $members profile was updated!"); 
} 
break; 
}
}
else
{
echo ("Sorry, but only Admins may view this page. Please go back!");
} 
?>

if ($logged[userlevel] == 6 OR $logged[userlevel] == 6) { //makes sure the user is an admin