hm sounds like something good for a journal....but to respond to your question, yes i have regrets.
As much as I don't want to live with regrets yeah~ they kinda just happen....somethings you can't turn back on. But there's a LOT that you can make up for or to make better. About your problems, you can still go back and try to fix them. Your firends, sisters, parents, all of them you can make up and try and resolve things.
Other things aren't so simple, sometimes you only get one chance with things....such as school and marks or relationships (like bf/gf relationships, not friendships), or to try out new things and meet new people. Those are the things I have regrets with.....
But always try and fix your regrets.....you DON'T want to lose sleep over something that you potentially could fix. Nor do you want your friends or family to be sad over those things either.