It can last for a very long time, don't be affraid to drop down in weight with the ball, I am going to 14's to save my wrist and it HITS just as well. Grips should be comfortably RELAXED not stretched, have a look at yours. It really is ok to have a little space between the palm and the ball, really i swear! It makes the game playable for some that couldn't before.
Overall, take a couple of weeks off, take some Ibprofen or other anti inflamatory a couple times a day and try not to lift weights much and it SHOULD heal up pretty quick.