Type Goch

well this is hard to describe so bare with me. It seems that these days, when i brake, it makes this soft click sound, from outside of the car. It feels as if its the suspension but im not sure. Say when im backing up, and i hit the brakes, the sound comes from the back(i think) and vice versa for the front. About a month ago, we did a brake pad change but didnt change the fluid, could that be an issue?
Thanks in advance
-James