Great job! You are doing all the right things. So glad that you had a BM. This is a good example of body throwing out what it does not need. People do enemas and I think body is designed to take care of all this. I have had BMs also on my 19th, 20th day in my fasts. Last fast, I had BMs everyday.
Good that you are drinking warm/ hot water, it will help in further cleaning.