Convinced herself she's pregnant?

Well, I have a friend, who has herself convinced she's pregnant and she can feel something moving and kicking inside of her. She hasn't taken any pregnancy tests because she still gets her period but she always says omg I just felt a kick or wow it feels weird but she refuses to go to the doctor. Her stomach hasn't changed but she's a big girl but its getting a bit constant and it all she ever talks about anymore so I'm getting a bit concerned and I just want to tell her to go to the doctor so they can tell her she's not pregnant.