This is probably what I will do from now on, jack the engine from the pan rails instead of the pan itself. No risk of screwing up the pan that way.
And yes, total complacency screwup. I'm glad it was at least something like this and not dropping the car on my head. I do still try to rock the car back and forth when it's set on jackstands to make sure it won't fall when I'm under it. EVERY time... I'm not trying to crush my skull.