Wow, smart girl.
If I were in her situation I don't know if I'd be able to figure it out, but I'm glad she didn't give up on trying to find what was wrong with herself.
It's not that uncommon to have something that goes undiagnosed for a long time, there are just some things that have vague syptoms and finding them is more to do with pure luck that anything.
That's what I think this was. Pure luck rather than 'outsmarting' doctors. It's not like she's studied the seven years or whatever it takes to become a doctor. She was just very determined to find out what was wrong with her. More so than any doctor who, lets face it see heaps of patients every week and probably have bigger concerns.
XD, naw, but seriously, wow... My dad has Crohn's disease... I never really looked into though. Hm.