For the last week my thumb and the palm under it have been sore. it pops frequently and now i can't bend it. ?

Trigger Finger: This sounds like a trigger finger which is a form of tendonitis. The most effective treatment is an injection of cortisone. See a hand surgeon.

Snapping thumb: You likely have a "snapping thumb." this is characterized by an obstruction of the flexor tendon. A local cortisone injection can often resolve this problem. A minor surical procedure would be curative if the local injection is not successful.

TRigger finger: Trigger finger is the result of the tendon that moves the finger has gotten swollen and is getting caught in its pulley. Treatments are conservative; oral anti-inflammatories, therapy and steroid injections. Surgical treatments include the open decompression of the pulley to allow the tendon to glide easily restoring motion.