Although I have never had that particular experience, it's not uncommon when you get slammed hard to feel it in the colon. It's also not uncommon when you lose consciousness to lose control as well.
So, yeah it's probably embarrassing. But it's not odd.
I told my kids, "Someday, you'll have kids of your own." One of them said, "So will you."
-- Rodney Dangerfield.