It sounds like it could be a TMJ problem, meaning Temporal Mandibular Joint. When you open and shut your jaw, do you hear clicking? Try putting you finger on the bone just under the ear, open and shut the jaw, does it feel funny, hurt, or make a "cracking" noise. Are you ears plugged of feel full. There are so many TMJ symptoms, I can not begin to list them, but, it sure can cause jaw pain, in fact, it can sometimes even cause upper chest pain. I would see an orthodontist, he will run some tests on the jaw area and be able to tell you more of what is going on.
Oh, do your clench your teeth or when sleeping, been told you grind your teeth? This is also TMJ related and will cause the jaw to hurt.
The hard part about teeth grinding is you never know you're doing it, because you're asleep. I once ground a hole in a feeling and never knew it. My wife will sometimes tell me in the morning that I was making awful noises and wonders how I even have any teeth left the way I can grind them.
As I was reading your post I was thinking like Susie was, either a cavity or TMJ or teeth grinding. Or even severe clenching of the jaw.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. Med Help International, Inc. is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.