Form: php validation help

programming
1

I am doing a test validation form, I am not getting the error message to display;
here is the code:

<?php
#-----CHECK SUBMITTION ----------
if (isset($_POST['action']) || ($_POST['action'] == 'submitted')) 
{
#-----CHECK IF NAME FIELD IS EMPTY----
 if (empty($_POST['name']))
 { 
  $message = "* Name is required";//exit;
 }
#-------CHECK IF AGE IS AN INTEGER AND EMPTY----
  if( (empty($_POST['age'])) && (!is_int($_POST['age'])) )
  {
   $message = "* Age is required";
  exit;
  }
 
 echo '<pre>';
    print "Name: ";
  echo $_POST['name']; 
  echo '<br>';
  print "Age: ";
  echo $_POST['age']; 
  echo '</pre>';  
    echo '<a href="'. $_SERVER['PHP_SELF'] .'">Back</a>';
    echo '</pre>';
} else {
//ERROR MESSAGE ($message) IS DISPLAYED BESIDE EACH FIELD IF RESULT IS TRUE//
?>
 
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post">
 <label>Your name: <input type="text" name="name" > <?php echo $message; ?></label><br />
 <label>Your age: <input type="text" name="age" ><?php echo $message; ?> </label><br />
 <input type="hidden" name="action" value="submitted">
 <label><input type="submit" ></label>
</form>
<?php
}
?>