I have a dull pain in the back of my thigh that comes and goes. should i go to my regular doctor? er? i keep hearing it can be blood clot.

See your PCP: Unless the pain is severe and sudden, there is no reason to go to the er. But you should have an examination done by your doctor as a starting point. He/she can order diagnostic tests if the pain is persistent or interfering with your normal activities.

Suggest ER: Birth control pill and cigarrettes are risk factors for dvt. If concerned er will be the quickest way to rule out a dvt.