What causes someone to compulsively grind their teeth ? i mainly do it when i don't get sleep but i cant control it it causes terrible sore jaw gums

Usually stress: No one can stop you from grinding or bruxing. Most of the time it is due to the different stresses in our life. In some cases grinding does become habitual.

Anxiety: is state of tension, apprehension, worry, uneasiness or fear. It may be related to anticipated danger or arise for no apparent reason. While mild episodes of anxiety are common and do not usually require treatment, more severe forms can be chronic and debilitating. Symptoms of severe anxiety: insomnia, chest pain, shortness of breath, nausea, palpitations, teeth clenching/grinding and headache.