I suggest making an appointment with a Neurologist!
Check your mattress. It's very possible a poor or hard mattress is cutting off your circulation. Also helps to fold and pillow and put it between your knees while sleeping, so that undue stress isn't put on your hips/knees, which can cut off circulation. Sounds to me like this is a circulation issue. Definitely look into a better mattress (I had same problem, new mattress fixed it!)