Why does my stomach do this? And second question...?

My stomach isn't fully flat; it has a little bit of a bulge to it, but whenever I eat, it suddenly bloats and looks like it's been inflated with air and it doesn't fully go down (hence the little bulge to it). It makes me really insecure to the point where I don't even eat because I don't want that bulge. Does everyone's stomach stick out like that after they eat? And why?

Also, as I said earlier, the inflation makes me insecure, so I tried making myself sick, but it wouldn't work. I tried using my finger, but it wouldn't go back far enough, so I got a toothbrush, but the most that would happen is my eyes would water, spit would come up, and I'd cough a lot, but I could never puke. Is that normal to not be able to make yourself sick?

Please don't give me any lectures about "being beautiful no matter what" or "making myself sick isn't the answer". I get that enough from my parents. I just want to know why my stomach sticks out and why i can't puke.

Thank you:)