รบกวนช่วยหน่อยค่ะ ตัดสต๊อกสินค้าแล้วมันตัดแค่รายการเดียว จะสั่งให้วนลูปยังไงค่ะ

<?

	session_start();
       include("connect.php");
	session_register("cart");  

	$order_id = $_REQUEST['order_id']; 

?>


<script>
     alert("·Ó¡ÒûÃѺ¨Ó¹Ç¹ÊÔ¹¤éÒ¤§àËÅ×Í㹤ÅѧÊÔ¹¤éÒ àÃÕºÃéÍÂáÅéÇ !!");
</script>


<?PHP
	
	foreach($_SESSION['cart'] as $p_id=>$qty)
	{
		$sql	= "select * from product where p_id=$p_id";
		$query	= mysql_query($sql) or die("error=$sql");
		$row	= mysql_fetch_array($query);
		$new	= $row['p_stock']-$qty;
	
		
?>
<?

$s1 = "update orders  set pay = '1' where order_id=$order_id";
$result0 = mysql_query($s1);

$s2 = "update product set p_stock = p_stock-$qty where p_id =$p_id";
$result1 = mysql_query($s2) or die ("error=$s2");


echo "<meta http-equiv='refresh' content='0;url=manageorder.php'>" ; 
?>

<?
  }	
  mysql_close();
?>