Ebbie, I'd strongly recommend that you do what I did - marry a chiropractor. Barring that, the Good Doctor (my wife) says that stretching is good for it, but that you really should see somebody. You may need work going up to your shoulder to relieve the cause of the pain. She can't say more without seeing you.
She does suggest that you spend some time stretching the finger between sets, and ice it afterwards. Self-massage on the hand, wrist, arm, and shoulder should also help. She can't tell if playing an instrument would do you more damage - she'd have to see to tell.
Good luck.
-Joe Offer-