@marybabe95,
Aren't you the same person who was really hit hard by some online person or persons saying you are too thin and look like a boy? I didn't look at your picture (I'll go back and do that) but you are taking that too excruciatingly hard and trying to fix it fast by stuffing yourself with poor food choices re nutrition.
I can't exactly guess why you have so little self esteem - many teens suffer from that. I was an appallingly ignorant teen - though smart enough in school, completely clueless about the larger world - but I got more confident when I went to a university that had a widely diverse student and teacher population.
Also working in a hospital after school opened my eyes a lot.
In both places I met people that were waaaay out of my comfort zone and we got along. Everyone there in the school - and also the hospital - was mostly not in an in-group (as in high school scenarios), and my sense of the world got, at the same time, much larger and more comforting for me with all the differences. I got very interested in other people and less zoned in on me.
So what am I saying? I think your gastritis is from your trying to please some idiots posting at you and become what you take (now) as more attractive.
Stop it.
Meantime, nutrition is an interesting subject. I recommend reading about it.
As usual, experts (so called, or real ones) vary on different nutrition issues, but you can learn a lot by reading up.
Also, I agree with Butrflynet - tell the truth to your doctor.