I have a 2020 BMW G310R and yesterday I was practicing U-turns. However I was dragging the rear brakes the whole time and after about 15-20 minutes I noticed a burning smell and I noticed that my rear brake pedal was able to be pushed down farther than it normally did. I got off and let the bike cool, and checked on the rear brake rotor and it appeared to have gotten really hot because there was blue and purple discoloration on it as well as what appeared to be burn marks. I was wondering if anyone would be able to tell me if my rotor is bad now or if the brake pads could also be damaged. And if so what should I do? After testing the rear brake at low speed it doesn't appear to be any less effective at stopping the bike than before.