I need to know if my shock is blown, my back right, when i go over bumps I hear a thump sound (sounds like the shock is compressing to much and hitting itself) i think, anyways, when I raise my car up a bit (ground controls) it does not do this, basically I think its compressed to far, does this mean my shock is blown? /could it be something else???

 

Its odd because i just had the car in for service and they didnt notice anything. When i raise the car up no problems, but i want to keep it low.