A bathroom dialogue

I had to take Hayden (the middle of my sisters boys) to the bathroom last night at church. The following conversation is from that event:

Hayden: (After using the word "poop") Oops...Mommy said I'm not supposed to say that.
Me: Poop?
Hayden: Yeah...even big guys aren't supposed to say it and especially big womens...cause they freak out.
Me: Gotcha

Come to find out this G-rated profanity "poop" was being used repeatedly by the pre-schooler and he was told that he wasn't supposed to say it anymore. Was I wrong in teaching him the term "fecal matter"?