Rhen

I have a 2020 C 43 AMG and I took away the resonators, put a straight pipe and put a down pipe. I liked the sound but it was way too loud on a cold start. I then went back a day later and put the resonator back and kept the down pipe. After I did this then an hour later while I was driving I noticed muffler hair was coming out of the tailpipes. The guy who did it for me (highly recommended) told me not to worry about it. Should I be worried at all?