The medical term for what you describe is "Paresthesia."
It is considered a neurological problem. You don't mention your age, but sometimes it can be caused by hormone imbalances. It can also be a side effect of some medications, street drugs, and even some supplements.
You might do some research on it based on anything you are taking. If you're not taking anything, you might ask your doctor to check your thyroid and hormone levels. A low-normal or high-normal result can be significant.
It could be due to anxiety....or your oxygen level is low...
Well sorry to hear that i know what its like going through the same thing my self but hang in there, here's hope and praying for some answer pretty soon have an appointment i'll make sure i let you know what they say and you should do the same, and dont't take i'm not sure from your doctor you need answers there not the ones fighting with this we are ok talk to you soon.