19 year old here, just finish my first year of school. So as someone who's recently changed a lot of my life and just left highschool, I'm gonna list my more serious regrets.
Not cutting my hair shorter. I had long hair that was not only a pain to maintain, but a lot of people didn't like (not to mention it was just goofy and winged out). It honestly looked stupid, but BECAUSE everyone wanted me to cut it, I took pride in not cutting it. I was such an idiot, cause so many girls straight up told me that they wouldn't date me because of my hair... I'm still known as "the guy with the hair", even though I've cut it short right before moving away for school.
Not losing weight. I was heavy, not overly heavy but 185lbs at 5'7 heavy, and I honestly thought that exercising was too much work, same with eating healthy. Second I moved away I started eating better and was 165lbs coming into this summer. It's ridiculous how easy it really is to eat better, and how much better you feel about yourself afterwards. I had some self-esteem issues you could say, despite me not showing it, and honestly losing weight really would have helped it.
Not playing so many god damn videogames. In my grade 12 year, I peaked at Diamond 1 40lp in League. I was ranked 2,500th in NA with over four months of gameplay across my accounts. Here's a hint, no girl cares about that, not employer cares about that, and the second you stop playing and get into real life you realized that you wasted four months of your life. I could have made so many apps building my portfolio making tangible things, which I would both enjoy and would better my future.
Exercise more. Going back to League, four months of raw gameplay over 5 years. That's 24 days a year of raw gameplay on average, 2 days a month or 1.6 hours a day every day. If I, one day a week decided "Let's only play for half an hour and instead spent an hour walking to the beach", that would be 240 hours of walking over those five years. FYI, that's 48,000 calories burned roughly, or 13 pounds lighter, by just playing 1-2 games less of League a week and going on a walk.