I Have Had A Bad Jaw For A While Now

I have had a bad jaw for a while now about 6-7 weeks, it comes and goes and i have also been to a dentist. He told me that i do have a nerve slightly showing and maybe after the fillings have been replaced (march24th 2016) however im getting the impression its not just my teeth its in all different areas and effects different areas at a time as it comes and goes. It feels like it aching. I have had past with drugs that make your jaw clentch i did about 2-4 years doing these drugs and have been clean now for 2 years. Is it possible i have damaged my jaw from this? Or is this signs of aomething else please help me get to the bottom of my problem
Many thanks
Jeff