Dropped iPhone 3GS with Otter Box

I dropped my iPhone 3GS from about 1 1/2 feet, with an otter box attached. Now none of the buttons work....I cannot turn it off, cannot change my volumer. When someone calls it does not ring however, I can see they are calling but I cannot accept or decline the call. I have a text message that is frozen on the screen, it pops back up after the calls hang up. It is still keeping time!

Any suggestions would be gretaly appreciated

Thnaks