I just had 2 tires replaced on my car. When they replaced the tires, the car was lifted with all 4 wheels off the ground. After the tire change was done, the suspension is bouncy as hell, the car also seems to be riding lower, and mudflaps are scraping speedbumps.

What could have caused this? The suspension was fine before i took it into the shop. I am taking it back to them tomorrow to check out, but i wanted some opinions on here as well. The car is a 2000 LS with 161000 miles on it, ive owned it almost 3 years, and it has the original shocks on it since i bought it, I dont know when/if the previous owner changed them.