Ive had a sharp pain in lower left side for going on a week. the er doctor ran every test he could think of but found nothing?

You should see a GI doctor-often this is an intestinal pain and it could be as simple as constipation. You may need more tests or perhaps a treatment could be tried-depending on any other symptoms you are having. So, see a GI doctor for evaluation and treatment. Good luck to you!

Follow up in the outpatient setting with your primary care doc will be needed, most such pain is musculoskeletal in nature and relatively hard to diagnose on imaging studies. Keep a log of your symptoms, circumstances for the pain, etc. that will help your doc formulate a better diagnostic plan.

Was any imaging done? may be diverticulitis (CT), kidney stone(Xray) or ovarian cyst(ultrasound) (or even release of the egg a mid cycle called Mittelschmerz or coming from the low back( sciatica-exam and MRI lumbar) . Rarely may be sprots hernia if you are athletic. Check that not pregnant and consider CT abdomen/ pelvis F/u/w/ MD