Anal sex

Hey guys. Recently me and my boyfriend had anal sex on my period. He ejaculated in me with no condom, so sperm entered me analy. I was wondering where does the sperm go when he cums in me through anal and how likely is it for the sperm to spill out into my vaginal area. We had anal sex on my period, and it was my second day (my period usually lasts five days) how likely is it for me to become pregnant? Thank you so much!