Dry humping without clothes

I was taking a bath when my bf followed me on the bathroom until we both heaten and try dry humping without clothes on. His penis didnt get inside, but I dont know if there is precum on his penis. I was so scared if it will lead to pregnancy. I am on cycle day 19 that time. Aunt flo is 12 days due. What are the chances.

Im trying to read some articles about it but also I want to know others opion. Please help me. Thank you.