A nice little app in progress

<?php

define('PUN_ROOT', './');
require PUN_ROOT.'include/common.php';
require PUN_ROOT.'header.php';
include PUN_ROOT.'tlhead.php';



//Make sure they use the form to access this page
if (isset($_POST['submit'])) 
{
    //Insert a new attempt MySQL is set to make sure only one new attempt is put in per day / per user
    $query = "INSERT INTO pun_contest (username, last_try) VALUES ('" . $pun_user['username'] . "', NOW())"; 
    $result = $db->query($query); 
    
    //If  they are allowed to enter a new attempt at this time 
    if ($result != $db->error) 
    { 
    echo "Your attempt has been added to the total."; 
    }
    //If they are not allowed to enter a new attempt at this time
    if ($result == $db->error) 
    {
    echo "You may only make one new attempt per day.";
    }
    //If they are the correct number to have tried, they win
    if ($db->num_rows($result) == 1)
    {
    echo 'Congratulations, you are the first.';
    }
}
else
{
echo "New challenges must be sent from the correct page.";
}
    
require PUN_ROOT.'footer.php';