A have a few regrets, all relating to my university years:
Choosing Computer Science as my major. I was (and still am) a computer geek who digs technology, but being a code monkey wasn't for me. I should have realized this by second year and switched programs to something I would have enjoyed more (like history, political science, or economics), but instead I stubbornly stuck it out until I graduated, which lead to...
...finishing university with a "C" average when I'd been a straight-A student from K-12. It was a vicious circle: I wasn't particularly good at computer science, so I did poorly at it, which in turn made me less motivated to double down and work harder. So I slacked through my courses, doing the absolute minimum I needed to do to pass. I wish now that I had tried harder and got better grades. While it's true that most employers don't give a damn what your GPA was, I have a feeling mistakes I made in my late-teens/early-20s will bite me in the ass if I ever want to go to grad school.
And a final, more comedic regret: not sleeping with more college girls when I had the chance. I'm now married to the most wonderful and amazing person I've ever met, but there's more than a few girls I could have shagged years ago but chose not to, and now I'm left wondering...
Listen to the advice of the old man from
Little Miss Sunshine.