K so im driving home from a date. My car sounds like ****. There was some knocking sound. so i was like damn i need to get that looked at. but while im driving the belt on the pulley near my alternator comes off (i dont know much but i think its my alternator belt) theres 2 belts. a small one and a larger one. the large one came off so i put it back on and see that it seems stretched out. Then i turn my car on and it comes off again.i try a few times more and same happens.the pulley has one large bolt holding it on and the pulley itself jiggles around a bit. so do i get a new belt or just stop the jiggling and replace the belt?

 

Tighten the bolt and put the belt on if the belt is stretched out to badly replace it.