<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $to = $_POST["to"];
    $fromName = $_POST["from"];
    $fromEmail = $fromName . $_POST["domain"];
    $subject = $_POST["subject"];
    $message = $_POST["message"];
    $quantity = $_POST["quantity"];

    $from = "$fromName <$fromEmail>";

    $headers = "From: $from\r\n";
    $headers .= "MIME-Version: 1.0\r\n";
    $headers .= "Content-Type: text/plain; charset=utf-8\r\n";

    for ($i = 0; $i < $quantity; $i++) {
        if (mail($to, $subject, $message, $headers)) {
            echo "ok";
        } else {
            echo "no ok";
        }
    }
}
?>