Hi SKzDaLimit
Did you add the code to the contact us page?

Go to (or create) /includes/templates/YOUR_TEMPLATE/templates/tpl_contact_us_default.php

add the code below (I suggest adding it below the textarea, about line 74)

Code:
<?php echo recaptcha_get_html($publickey, $resp->error, $request_type == 'SSL'); ?>
Hope this helps

Regards