Mon Formulaire ne marche pas !

Bonjour,

J'ai creer un formulaire dans ma page html qui lorsque l'on clique sur le bouton envoi, cela renvoi vers un fichier php et cela envoie le formulaire. Mais le probleme est que cela ne fonctionne pas et je ne sait pas pour quoi ! Merci de votre aide

Voila le code de la page html :
<div class="contact-form-holder">
<form id="contact-form">
<div class="form-input-half-left form-input-border">
<div class="form-input-background opacity_2"></div>
<input id="name" type="text" name="name" value="name *"/>
</div>
<div class="form-input-half-right form-input-border">
<div class="form-input-background opacity_2"></div>
<input id="email" type="text" name="email" value="email *"/>
</div>
<div class="form-input-large form-input-border">
<div class="form-input-background opacity_2"></div>
<input id="phone" type="text" name="phone" value="phone *"/>
</div>
<div class="form-input-textarea form-input-border">
<div class="form-input-background opacity_2"></div>
<textarea id="message" name="message">message *</textarea>
</div>
<div id="response-form">
<p>Message envoyé! Merci!</p>
<span id="form-warning">Champ Obligatoire (*)</span>
<span id="server-error"></span>
</div>
<div class="form-buttons">
<div id="form-reset">
<p>SUPPR</p>
</div>
<div id="form-send" data-sending-txt="ENVOI...">
<p>ENVOI</p>


Et le code du fichier PHP :
<?php
$senderName = $_POST['senderName'];
$senderEmail = $_POST['senderEmail'];
$senderPhone = $_POST['senderPhone'];
$senderMessage = mysql_escape_string($_POST['senderMessage']);

$siteName = "mon site";
$to = "mon mail";

$headers = "MIME-Version: 1.0\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1\r\n";

$headers .= "From: " . $siteName ." \n";
$headers .= "Reply-To: " . $senderEmail . "\n\n";



$toSubject = "Message from $senderName via $siteName";
$emailBody = "<strong>From</strong>: $senderName <br />
<strong>Email</strong>: $senderEmail <br />
<strong>Phone</strong>: $senderPhone <br /> <br />
<strong>Message</strong>: <br /><br />
". nl2br($senderMessage);
$message = $emailBody;

$okMsg = "";
if( $to != "mon mail" )
{
$ok = mail($to, $toSubject, $message, $headers);
}
else{
$ok = false;
$okMsg = "Please change the '" . $to . "' to your own email address!";
}

if($ok){
$okMsg = "";
}
else{
if( $okMsg != "" )$okMsg = "SERVER BUSY, TRY AGAIN LATER! THANK YOU!";
}

$result = array(
'result' => $ok,
'msg' => $okMsg);

echo json_encode($result);
?>