The top of my forearm, 2 inchs above my wrist hurts when i move my thumb or my wrist. what could this be?

Intersection syndrom: This is known as intersection syndrome. It developes secondary to tendonitis in the 2nd and 1st extensor compartment. The pain arises at the point where the 1st extensor compartment tendons pass over the extensor carpi radials tendons resulting in pain with thumb motion, and wrist motion. This is an overuse syndrome that usually responds to conservative modalities like splinting, and therapy.