<?php
    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From: mail@adresata.pl';
    $to = 'twój@mail.pl';
    $subject = 'Null graphics';

    $body = "From: $name\n E-Mail: $email\n Message:\n $message";
?>

<?php
if ($_POST['submit']) {
    if (mail ($to, $subject, $body, $from)) {
        echo '<p>Thank you for your email!</p>';
    } else {
        echo '<p>Oops! An error occurred. Try sending your message again.</p>';
    }
    header('Refresh: 3; url=kontakt.html');
}
?>