What is your most devastating instant regret experiences?

I was hunting rabbits and quail once on a farm we didn't own but had permission to hunt on and snow was about 20" deep after a big storm. I needed to pee..........so I did on a big tree and though I didn't know it at the time......an insulator for an electric fence was nailed to that tree. The electric fence was on..........and I pretty much INSTANTLY regretted taking a pee in that particular spot.