Regret it

Why do we regret things? As you probably have gathered from previous posts, I'm reading Hamlet in my English class. Today we got the scene where Claudius expresses his regret for murdering his brother [I know, he's such a butt-head!], and I started thinking about regret [English is such a good time to reflect upon things...] and why we regret things. I personally don't believe in regret for the right reasons [for something they chose to do]. I don't think that someone can really feel... remorse I guess... sure you can be sorry you got caught, or you're experiencing well deserved consequences; but the reasons why you did something [again, something you did by choice] will always stand. You can regret getting drunk and driving and killing someone, but you can't really say you feel regret for punching the kid who calls you fat every day. Sure you'll regret doing it because you get caught, have bruised knuckles, and possibly start a brand spankin' new criminal record, but you're still going to feel good that you put that jerk in their place. Just saying. Don't worry, Mum, I didn't punch anyone.