Why am I having so many gastric problems? (Acid reflux, diarrhea, upset stomach.)?

I recommend staying away from over the counter medication like Pepto. A year and some months ago, I had almost exactly the same symptoms you are experiencing..diahrrea, vomiting, upset stomach..Nothing would stay down. Turns out, it was a stomach virus. Are you feverish?Sometimes you might not feel feverish but still have a stomach virus, which is what happened to me in the beginning. I ended up losing 10 lbs over the course of three weeks. According to the doctor, the over the counter medication exacerbated the situation by making my stomach lining more irritable. Also, try not to take any Ibuprofen when feeling ill to your stomach. It thins your stomach lining and can cause further damage if you have a bug. Another thing: I had my gall bladder removed this past October. I had similar symptoms to what your describing. In addition to your symptoms, do you have intense pain after eating (especially greasy foods)? If so, you may have to get your gall bladder checked out. My best suggestion: go to the doctor. If he/ she doesn't solve the problem, have him/her refer you to a Gastroenterologist.