Last week I removed the calipers to do a spring swap. When I went to put the calipers back on I had to push them apart to fit over the rotor. To do that I inserted a long screw driver and levered the pads apart. They then fit over the calipers. So I tightned everyhing down and pumped the lever to build pressure. Everything seemed fine at first but now my front brake seems weaker than before. Any thoughts? Could I have scratched the pad surface with the screw driver? Would that cause weaker breaking? The fluid was flushed a month ago so that's nice and fresh.