Sending a message

Ok so I have tried to create a sort of messaging system on my website and I have run into some problems storing who the message is from, ill try to take you through step by step what I am trying to do. step #1 (messages.php): <--This is where the member will view the recent messages that have been posted <div id='messages'>

           <?php
           include 'connect.php';
           session_start();
           $_SESSION['user']=$user;
           //store sql queries
           $sql="SELECT * FROM entries";
           $result=mysql_query($sql, $con);
           $count=mysql_num_rows($result);
           if ($count<1){
               echo 'There are no messages yet!';
           }
           while ($row=mysql_fetch_array($result)){
               echo 'From: ' .$row['from'];
               echo '<br/>';
               echo 'Subject: ' .$row['subject'];
               echo '<br/>';
               echo 'Message: ' .$row['body'];
               echo '<hr/>';
                     }
           ?>
       </div>

Step #2 (create_message.php):<-- This is where the user creates a new message <h2> Create new message</h2>

           <table border='0' width='100%'  cellpadding='3px' style='text-align: top;'>
               <form method='post' action='insert_message.php'>
               <tr width='100%' height='30%' style='margin-top: 0px;'>
                   <td> Subject </td>
                   <td> <input type='text' name='subject' maxlength='30'></td>
               </tr>
               <tr width='100%' height='30%'>
                   <td> Body </td>
                   <td><textarea name='body' style='height: 200px; width: 400px;'></textarea></td>
               </tr>
               <tr>
                   <td colspan='2' align='center'><input type='submit' name='new_message' value='Send!'/> </td>
               </tr>
               </form>
           </table>

Step #3 (insert_message.php)<-- this is where my problem is (trying to insert $_SESSION['user'] into table ['from']) <?php include 'connect.php'; session_start(); $user=$_SESSION['user']; if ($_POST['new_message']){ include 'connect.php'; session_start(); $_SESSION['user']=$user; $body=$_POST['body']; $subject=$_POST['subject']; $date=' '; $sql="INSERT INTO entries ( id , from , subject , body , date ) VALUES ( NULL , '$user', '$subject', '$body', '$date' )"; if (mysql_query($sql,$con)){

       echo 'Inserted!';
       echo $user;
         }

else

       echo 'Not Inserted';
  }

?> Hope i dont piss anyone off with such a long message, I just really need help on this. Thanks!