Oh, that's classic! When there really is something wrong, the last thing you want to hear is that it's all in your head.
I've a lost a friend or two over the years to real problems that were dismissed by a tired doc.
You just hang in there, and thank your lucky stars you've got a good lady to listen to you.
I go to a teaching hospital, and, at this point, most doctors are younger than I, inspiring another piece of advice - if you're older than your doctor, you can give him plenty of lip. If he can't take it, leave him.