I drop my car a few months ago and lately I every time I go over a speed bump there is noise coming from the back of my car.. it sound like something is hitting the exsust pipe

 

well, if it was hitting your exhaust, you'd hear a scrape...

 

Go back and make sure all your bolts are torqued correctly...

 

yeah i had a similar prob b4 i lowered my car, i got under it to take a look at what was going on and a bracket on my exhaust had rusted off, i removed it, the noise is gone. im not in a rush to replace it but i probably should sometime soon