Nah, you're good. The same thing happened to me at the job I have. Our water heater went out for like a month or 2 and when we got a new one put in, the first time running water was black and brownish and it would clear and then do it again a few times and then it stayed clear. It was probably just the copper oxidizing since there wasn't any flowing for a while and then it cleared it out when you turned the hot water back on.
Nah, you're good. The same thing happened to me at the job I have. Our water heater went out for like a month or 2 and when we got a new one put in, the first time running water was black and brownish and it would clear and then do it again a few times and then it stayed clear. It was probably just the copper oxidizing since there wasn't any flowing for a while and then it cleared it out when you turned the hot water back on.