I Am Having Severe Left Jaw Pain. I Have Been

I am having severe left jaw pain. I have been to a dentist, endodontic dentist, primary doctor and the emergency room and none of the tests have revealed any problems. I had x-rays of teeth, root canals and face. I also had a CT scan and EKG but everything seems to be normal yet I am still having major pain even though I have been prescribed pain pills.