If you are getting to the thank you page then it indicates that the server behavior is being triggered properly. Have you tested out more than one email address to send the email to?
The most common issues that I see when the email does not arrive are the recipients mail box is filtering the email out, or the settings that are used for the mail server are not correct. What are the settings that you are using for your mail server? Do you know if this is the correct value to be using? Usually your host will have settings that you can use to access an SMTP server that will allow you to send emails.