My lower jaw is "sore" and kind of heavy, and has a tired feeling. i clutch my teeth of the side of my cum, it gives it a rest. what is causing this feeling? wisdom tooth? tmj? what specialist so i see to evaluate this, dentist?

Start with your regular dentist, then, once jaw and dental issues are specified, take the next step.

Sounds like it's been quite awhile since your last dental evaluation. Your reported symptoms are rather vague. Best advice, see a Dentist now. You may har infection, parafunctional habit, malocclusion, etc. You will have to be physically examined, probably x-rayed, and will perhaps need lab tests.