anal sex,ejaculation in bottom

me and my boyfriend just did anal sex and i let him ejaculate in my bottom for first time and after i made sure it was cleaned up and i went to toilet and pushed so all would come out and i pooped alittle anyways.... i’m just worried about if there was more in there and what to do not to get pregnant if there was leakage at some time??

> i’m not on any birth control

>no semen leaked anywhere near my vagina

> and i cleaned and tried as much as possible to get everything out of my bottom