What did you enter for the to address?
What did you use for the from address?
the from address needs to be a valid email address for the domain.
to trouble shoot, add the following code on the success page in the body:
<?php @session_start(); var_dump($_SESSION); ?>
this will write the session contents to the page including the status of the email.
post a link where i can see this please.
also, the email may be in a spam folder, so don't forget to check your spam folder.