Normally these shocks are able to take speeds up to 7-8 miles per hour and the platic bumper cover is also very absorvative, so there should be no damage. To be sure pull it of, it' s just five minutes, and check if thre are any visible cracks in the paint under the bumper around the shock mountings and at the corners . It often happens that the bumper gets pushed up to hitting the body and damaging the paint which is not visible due to the bumper being in place, but comes to show as rust bubbles a few months later.