My heater/ac hasn't worked at all this year, but today i still put it on bc the window was fogged a little and hoped that a little bit of AIR would come out of the defroster well nothing came out but then suddenly i hit a pothole and the car started making a really loud/annoying sound, and the vents blew air out and it was hot. Does anybody no whats wrong with it... the heater works once again but it also makes the loud noise!
thanks...

 

Might need to replace the blower motor.

 

I agree with DetroitMuscle.
The brushes were probably stuck on the armature 'cause they're worn. You had the fan turned on and hit a bump to jar them loose and conduct the electricity. Same thing would have happened if you had it turned on and hit the end of the motor with a screwdriver handle.
So, now it make a wierd squealing kinda noise?