php - AJAX Contact form - not working properly -

i've created simple ajax, jquery, php contact form on website inputs: name, email , message. problem when write actual email email field message never comes inbox. works when email input field contains 1 word no @ sign.

my html:

<p class="form">name</p> <input type="text" name="username" id="username"> <p class="form">email</p> <input id="useremail" type="email" name="useremail"> <p class="form">message</p> <textarea id="msg" name="msg"></textarea><button onclick="sendcontact();"></button> 

my javascript:

function sendcontact() {      jquery.ajax({         url: "contact_me.php",         data:'username='+$("#username").val()+'&useremail='+         $("#useremail").val()+'&msg='+         $("#msg").val(),         type: "post",         success:function(){             sendsuccess();         },         error:function (){}     }); }; 

my php:

<?php $to = "dusset@gmail.com"; $from = $_post['useremail']; $name = $_post['username']; $subject = $name . "has sent message .design"; $message = $name . " wrote following:" . "\n\n" . $_post['msg']; $headers = "from:" . $from;  mail($to,$subject,$message,$headers);?> 

any idea problem, please?

try changing how pass data ajax. example:

function sendcontact() {     jquery.ajax({         url: "contact_me.php",         data: { username: $("#username").val(), useremail: $("#useremail").val(), msg:  $("#msg").val()},         type: "post",         success:function(){             sendsuccess();         },         error:function (){}     }); };