I don't believe that for a second. Secondary school (our equivalent) svcked. University was the best days of my life so far.
Since I dropped out of college, (like an idiot) I can't speak there, But as someone who's had over twenty years to think about his high school years (I hated them back then), In retrospect, those WERE the best years I had. I only wish I knew then what I know now.
Regrets? yeah I got em. Mistakes? made lots of em.
It's amazing what a little age does to someone. The way you feel about something now, is not necessarily how you will feel about it in ten or twenty years.
Enjoy these years, you will never get them back once they are over, and memories are all that are left.