Severe lower left side abdominal pain past 7 days. vomiting and diarrhea. no appetite very weak. nothing relieves pain. what could this be?

See a doctor: Many different things can give u those symptoms. Diverticulitis, viral or bacterial colitis, tumors, adhesions/obstruction, gyne cysts or infections, less likely cancers can all give u sharp lower abdo pains. Is anyone else sick? Any tainted food or water? I would see a physician asap. He/she will be able to examine, take a good history, obtain images. If it really is "severe" go to er tonight.