My left hand hurts right above my wrist i am left handed i can't use my thumb as much as i could before it hurts to touch and it is akey?

A common type of: Tendinitis that affects this area is dequervains which typically resolves with anti inflamm stories and or a soft splint that includes the the thumb and wrist , at times a corticosteroid injection and rarely surgery. Starting out with simpler treatment and avoiding extremes of motion is the first step .A hand surgeon can help.

DeQuervain's disease: Sounds like this disease named after a french doctor who described it in the 19th century. The thumb tendons coverings are swollen and irritating the radial nerve yielding pain. The first step is to be examined by a specialist. He may be able to cure you with a cortisone shot.