Sending a mail via ajax with a captcha

app.js

$('#submit').click(function(e) {
		// e.preventDefault(); 
		console.log('clicked submit');

		var $errors = $('#errors'),
			$status = $('#status'),

			name = $('#name').val().replace(/<|>/g, ""), // no xss
			email = $('#email').val().replace(/<|>/g, ""),
			msg = $('#message').val().replace(/<|>/g, "");

		if (name == '' || email == '' || msg == '') {
			valid = false;
			errors = "All fields are required.";
		}

		console.log('captcha response: ' + grecaptcha.getResponse()); // pretty sure the problem is in this line

		if (!errors) {
			// hide the errors
			$errors.slideUp();
			// ajax to the php file to send the mail
			$.ajax({
				type: "POST",
				url: "http://orenurbach.com/assets/sendmail.php",
				data: "email=" + email + "&name=" + name + "&msg=" + msg + "&g-recaptcha-response=" + grecaptcha.getResponse()
			}).done(function(status) {
				if (status == "ok") {
					// slide down the "ok" message to the user
					$status.text('Thanks! Your message has been sent, and I will contact you soon.');
					$status.slideDown();
					// clear the form fields
					$('#name').val('');
					$('#email').val('');
					$('#message').val('');
				}
			});
		} else {
			$errors.text(errors);
			$errors.slideDown();
		}
	});

index.html

<form class="form" action="javascript:void(0)" novalidate>
	<!-- all the inputs... -->

	<!-- captcha -->
	<div class="input-group">
		<div class="g-recaptcha" data-sitekey="6LdOPgYTAAAAAE3ltWQGar80KUavaR-JblgPZjDI"></div>
	</div>
	

	<div class="errors" id="errors" style="display: none"></div>

	<div class="input-group">
		<input type="button" value="Send" class="btn-default right" id="submit">
		<div class="clear"></div>
	</div>

</form>

sendmail.php

<?php
	// my email
	$email_to = '[email protected]';

	// getting the data from the post
	$name = $_POST['name'];
	$email_from = $_POST['email'];
	$msg = $_POST['msg'];

	// subject of the email I'm going to get
	$subject = 'Message from $name';

	// make the message I'm going to see
	$finalMsg = 'Email from $email_from\n';
	$finalMsg .= 'Message:\n\n';
	$finalMsg .= '$msg';
	$finalMsg .= '\n\nTo respond, send him an email.';

	// getting the captcha
	$captcha;
	if (isset($_POST['g-recaptcha-response']))
		$captcha = $_POST['g-recaptcha-response'];
	echo 'captcha: '.$captcha;

	if (!$captcha)
		echo 'The captcha has not been checked.';
	// handling the captcha and checking if it's ok
	$secret = '6LdOPgYTAAAAAPSWpxQ7xks9yJPYNsNE0XNHSxTc';
	$response = json_decode(file_get_contents("https://www.google.com/recaptcha/api/siteverify?secret=".$secret."&response=".$captcha."&remoteip=".$_SERVER['REMOTE_ADDR']), true);

	var_dump($response);

	// if the captcha is cleared with google, send the mail and echo ok.
	if ($response['success'] != false) {
		// send the actual mail
		@mail($email_to, $subject, $finalMsg);

		// the echo goes back to the ajax, so the user can know if everything is ok
		echo 'ok';
	} else {
		echo 'not ok';
	}

	// @mail($email_to, $subject, $finalMsg);
	// echo 'ok';	
?>