stomach pain on left side by belly button

Hi, I just joined here. I'm 16 years old (female; normal weight->123 @ 5'3"), and I've been having pretty bad stomach pain for years now, but it's progressivly changed.

Since November 08, I've had this pain. It was in my right lower side at the time. I went to the hospital for that, thinking it was appendicitis, which is wasn't. I had some sort of scan (don't remember what it's called, but I had to drink barium), but nothing showed up. I went to a chiropractor the next day, and he said it was a virus in my appendix, and put me on probiotics. It helped, and when I stopped taking them, the pain started once again, but didn't last for long. I don't know if this info would help any, just thought I'd mention it.

The pain started again last year, in November 09. It's diffent though.

My parents call me "Pepto" now because of how I chug pepto bismal minutes after we eat. It's not working any more though. The pain has gotten worse, and is lasting longer now than it was over the holidays. After I eat anything, 15-30 minutes later, my stomach hurts so bad. It starts out feeling crampy, then goes to a not dull, but not sharp pain. It starts on the upper left side of my abdomen, right under my ribs and by my stomach, then moves to under my belly button or around the left side of it. The pain stays in the left middle side from then on. It's worse in the morning, I've noticed. For the past few days, it has been waking me up in the morning, like an hour before I usually wake up. My stomach feels distended (it's not though) after I eat, even just a small portion, like just the cheese off the top of a slice of pizza. I also feel very nauseated for hours after. I've noticed my stomach hurts when it is empty as well.

I've been experimenting with different foods recently to see which ones make my stomach hurt the worst. Yogurt, milk, chocolate, meat, bread, vegetables, fruits, and pretty much everything else makes it hurt. Those are the worse. And no, I do not believe I am lactose intolerant. I can eat dairy sometimes (like cheese pizza) and I'm fine. But other times (like a yogurt for breakfast) puts me in severe pain.

I'm so sick of dealing with this pain. I'm going to a pediactirc gastroenterologist Monday afternoon, so we'll see if that hurts. I've been trying to figure this out myself though. If you have any questions, just ask! Thanks so much!