PHP login with PDO, doesnt seem to work

PHP login with PDO, doesnt seem to work

There aren't any errors given, but for some reason the code doesnt seem to
work..
Here is the code:
<?php
session_start();
require_once('inc/db.php');
if(isset($_SESSION['username'])) {
header("location: index.php");
} else {
try {
$username = mysql_real_escape_string($_POST['username']);
$password = mysql_real_escape_string($_POST['password']);
$SQL = $dbh->prepare('SELECT * FROM users WHERE username
=:username AND password =:password');
$SQL->bindParam(':username', $username);
$SQL->bindParam(':password', $password);
$SQL->execute();
$total = $SQL->rowCount();
$row = $SQL->fetch();
if($total > 0) {
if($row['verified'] > 0) {
$_SESSION['username'] = $username;
} else {
echo "Unverified";
}
} else {
echo "Incorrect";
}
} catch(PDOException $e) {
}
}
?>
Can anyone help me see what's wrong? Thank you a lot in advance :)
EDIT::::
Here is my db.php
<?php
try {
$DB_NAME = 'users';
$DB_USER = 'root';
$DB_PASS = '';
$dbh = new PDO('mysql:host=localhost;dbname='.$DB_NAME, $DB_USER,
$DB_PASS, array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e) {
echo "Error?";
}
?>