I hope this wasn't a choice, bad or otherwise. Sounds like you weren't in control.

And if you can lose control, and get repeatedly violent with a random non-threatening stranger at the zoo of all places.. and your response was to run away, and take no responsibility for it?

I'm sure you mean well, and are generally great. But anger of this magnitude over something so small as a parking spot? How are you going to prevent it from happening again?

I'm not trying to make you feel worse, but what exactly did you learn from it? Why do you think punching someone over a parking spot was even in the realm of possible outcomes for you in this situation?