Your not an a** but maybe the subject needs to be approached differently if you haven't done so just be on her side, I didn't read how long you've been dating so I dont know if it's serious but if you love her let her know your believe her and that your think she should see the doctor maybe before you do anything else I believe if she sees that you believe her and your serious ,she'll go, she needs to . Hopefully it's nothing bad . Sometimes different or certain positions can hurt. And if there's nothing wrong with her but she keeps it up you go from there . But even if you assumed it was fake telling her you think that it was may not have been the best approach. Good luck.