in the middle of session... auntie comes

Mm has period and we get all the stuff all over... the bed/me. What do you do?? Never happened to me before. was about 30 min into the session. Didnt want to stop at first but as I came to my sense I stopped. Still was messy. Should I be worried about anything? I am not going to complain. Mm was very sweet. I stayed almost 2 hours after with mm after time was over.