tired of feeling horrible.

I posted a topic on another forum, but haven't gotten any responses yet, so hopefully someone can help me. For the past 3-4 months, i've had diarrhea everytime I have a bowel movement. It's sometimes just soft and has been bright green on occasion. In addition to diarrhea, I also have severe cramps and the past week or so I've had an occasional sharp shooting pain in my right side that usually lasts a few minutes before it stops. Also, I find that i'm nauseous a lot as well and often gag but hardly vomit. I decided to finally go see a doctor about this, after telling him about the sharp pain, he felt my stomach and when he applied pressure to the area where the gall bladder is, it was extremely tender and painful. The doctor suggested I go get an ultrasound, which is what I did this morning. The nurse called me and basically said everything checked out fine, which I guess means that I did not have gall stones. However, the doctor mentioned that if I did not have gall stones I still may need to have my gall bladder removed. He said there is some sort of test they do that measures the percentage your gall bladder is functioning. I haven't heard from the doctor yet, and I'm not sure what I should do. He gave me a prescription for the diahhrea and cramps, but I have to say I don't feel like the cramping medicine is helping much. I still have cramps, they're just not as intense. I hope someone can offer some advice as to what my next step should be as far as treatment goes. I'm just tired of constantly feeling terrible, is it possible the problem isn't my gall bladder at all? I just really want to figure out what is wrong with me