Glazed brake. Am I fixing it correctly?

A few weeks ago I did Brake job. I replaced the pads and 3 rotors. I found that one of the rear calipers had seized when I drove about five miles and was overtaken by a cloud of smoke. I replaced that caliper the next day. Now, when coming to stop, in the 10 to 3 Mph range that wheel moans at approximately 500 Hz. I ume the heat glased the pad and perhaps coated the rotor with something like carbonized brake fluid. I've never had this problem before (in 33 years of working on cars) but I plan to take off the rotor and pads and give them a light sanding with 120 paper. I don't feel like buying a new set of pads and taking the other side apart too.