Take it off my chest

Okay so while having anal sex with my boyfriend around two weeks ago he found poop on his dick( disgusting I know) since then I feel so bad and i still can’t stop thinking about it because it didn’t happen before ( we have been together for over a year) I have literally lost interest in sex and I feel disgusting.

he was sweet he acted like nothing happened thats what he shows but I’m afraid that deep down he thinks that I’m disgusting and that he lost interest in me:(