Woke up with arm numb from elbow to fingers, thumb and first two fingers affected what could this be?

Nerve encrouchment. Sounds like you slept in a position in which pressure was being placed on nerves which then produced the symptoms you are referring to. If this has cleared up then you might alter the position in which you sleep. If not, consult with a neurologist. Good luck and get better.
See your doc. You need to see your fam/doc or refer you to neurologist and test you for vascular and nerve conduction to see the cause is vascular or neurological due to nerve compression in your neck or thoracic outlet shoulder or elbow andfurther down? The once DX is made treat you properly.
Cervical disc nerve . This may be due to sleeping with your neck in an abnormal position which can cause nerve compression.

Related Questions

Painful lump r armpit 49 f dental hygienist general aching r arm numb fingers r wrist neck bicep thumb middle & ring joint swelling on & off 3-4 month?

Need evaluation. You need an examination by a hand specialist or neurologist to make the correct diagnosis. Read more...
Cervical pressure. This could be related to pressure on your cervical vertebrae , if the nerve is under pressure it could send numbing sensation into your arms and fingers, it is affecting you r side. You need to see an orthopedic surgeon and get it diagnosed properly. Hope you get better. Read more...