Tonight it was raining, so on the way home from work i stopped to do doughnuts in the school parking lot. I got the car to go around 180 degrees and that stalled and killed the engine. After 2 tries I got the engine to re-fire, but the battery warning light came on on the dash and the alternator wasnt charging. I popped the hood and the belt is still on and working. Any ideas on what may have caused this?