Taking it too far

Why is it that kids can't stop themselves? When do they learn self-control? I try not to nag my kids (their father does that enough) but give them a warning that something might be dangerous or painful or lead to unpleasant consequences. Today, my daughter was wearing crocs and decided to slide on the ice in the middle of the street with her friend. I told her to be careful, that her shoes would make her slip and that she'd probably fall. Of course, what happened? Yup - splat right on her face. She waited till she got in the car to cry, and did so all the way home and then while laying on the couch. I know my kids don't like to listen. Why is it, though, that a tickle has to turn into a wrestling match that ends with punches to the gut and kicks to the ribs? Or standing next to someone leads to a game of tag that leads to shrieking in public places and bumping into unsuspecting passersby? They take everything too far. I don't think I'm that strict. I don't think I limit my kids too much. I may be wrong. I've been told by some that I'm too hard on them and by others that I'm not hard enough. I don't want to stymie their free spirits, but come on. I let them "swim" in the bathtub tonight. They had bathing suits on, a ton of toys, foam spray for the walls, and on and on. That wasn't good enough, apparently, because the game became splashing and soaking the shower curtain, walls, ceiling, floor, toilet, towels, toilet paper and anything else they could reach. Too far. So when will my kids get that internal stop sign? Or at least a yellow light so they'll slow down.