I always feel sleepy. also feel like crunching my teeth tightly. what is wrong with me? i usually sleep at 2200 and wake up at 0645.

Possibly Sleep Apnea: You may have obstructive sleep apnea, or "osa". If you're sleepy during the day, you may be waking up at night because of difficulty breathing (obstruction possibly caused by several things). You should get an official sleep study, prescribed by your doctor or a pulmonologist at a sleep center. Osa is a risk factor for high blood pressure, stroke, and heart attack. Get this checked out.

Probably stress: Sleeping from 10 to 645 is a good amount, but you may not be getting restfull sleep--not enough deep sleep. Teething grinding is a sign of higher stress and so make sure you find the cause and manage it. Eat healthy and increase aerobic exercises and help reduce your stress and improve sleep, which in turn will decrease your fatigue. If worsens, see your doc.

Teeth Clenching: Sounds like you are clenching your teeth at night which is a common habit. I would see your dentist. He may make you a specila appliance to wear at night so your jaw muscles will relax