Yes, I belatedly noticed I've made a poo-poo there but I find it difficult to think they are completely separate entities anyhow...
It's bad manners to correct other people's English, I know, but this one could cause you embarrassment if used in conversation - a mistake is a "boo-boo". A "poo-poo" is excrement. (Just to add to the confusion, to "pooh-pooh" something is to dismiss it out of hand - there's an episode of
Blackadder Goes Forth that has a lot of fun with the homophone.)