Headlights

I cleaned my headlights with the 3m medium duty headlight polishing kit and when I
finished my headlights would not turn on at all I didn't touch any wires while doing this but
obviously it shorted out somehow, I have checked all my fuses and replaced the relay
more than once, the first time I did the headlights worked for the rest of that day then
stopped, the second time I replaced the relay they worked for about an hour then stopped,
now I've replaced it again and they won't turn on at all but when I flip the switch a loud
clicking/buzzing sound comes from the fuse box under the dash, (once again I checked
the fuses still no problem) I have even tried looking for some exposed wire but came up
empty, have switched the bulbs and anything else I could possibly think to try, Please help!