Anal... how to not sh*t?? Apologies in advance

Right this will seem pretty gross.

But every time I try to have anal sex with my man I feel like I’m going to shit all over him, even when he only puts a little finger in. I know this is an expected feeling but how do I basically not shit or get rid of the fear that he’s going to end up with shit on his finger or dick?

We’re yet to get all the way with anal sex because I freak out about it.

APOLOGIES FOR THE GROSSNESS LADIES!!!! I am very sorry! Just need advice lol!

Not sure if I should invest in a douche or what