This past weekend I changed the brake pads in my girlfriend's 2007 Acura RL and after a successful job, the suspension is not riding the same. It rides like I have lowering springs on it, what is the problem?

 

How many miles are on the car? I vaguely remember reports of struts going back on this car after it was sitting on a lift overnight with the tires on it, possible the struts went bad?

I'd start with the simplest explanation, remove the tires and inspect, is everything put together correctly?

 

Yup, quite possible, recently had an A13 service done and they had the car on a lift. Now the suspension feels like it went bad. The ride quality is now noticeably different.