Sudden sharp shooting jaw joint pain radiating to the ear and felling of blocked ear. All from bruxing?

TMJ. This sounds like TMJ (tempromandibular joint) pain. This joint is where the lower jaw moves with the upper jaw - in front of the ear. People can grind this joint with eating or with stress. There is mal-alignment. This is called bruxism - grinding, gnashing or clenching your jaw. Some do this at night. The use of a jaw guard at night can help put the jaw into appropriate alignment.
Possibly. All those symptoms could be from bruxing. There are nerve reflexes in the jaw area that could cause all of those issues. You still need to have the teeth , ears. And sinuses looked at to be thorough.
Could be. could be. Could lead to more serious problems. See TMJ expert. Any dentist can be a TMJ expert with the proper training and experience. Most commonly, oral surgeons, prosthodontists, and orofacial pain specialists. Ask your MD, your dentist and your dental society for referrals.