38f healthy. hands fall asleep while i sleep at night. happens mostly when arm is at full flexion. do i have some sort of peripheral nerve damage?

Impingement: This appears to be a very positional symptom where full flexion of your arms results in impingement of nerves entering your hands and extension of arms relieves the impingement. Another possibility is a carpal tunnel syndrome, but I would expect hand tingling or numbness on other occasions as well. A hand surgeon or neurologist can evaluate and advise you if you still have concerns.