If the PHP code is called without GET request the server produces an warning-error because $_GET['email'] do not exist
The script should still function but it is better to check if the GET-Request ['email'] and ['senha'] exist
$email = $_GET['email'];
I meen the function 'isset()' ...
The variable for the e-mail will be delivered only if a GET-Request exist ... the AJAX code prevents this already, but for a good and safe programming you should not trust on it.