Sometimes, for example when you're at work, you feel like time doesn't pass at all. You look at the clock and only 10 minutes have past since the last time you looked. But it feels like an hour to you. At the end of the day you go like 'today was a long day'.
But years go fast. Every new-years eve I think about how fast it all went. Don't you ever have that? When you think about something and suddenly realize that it happened a year or two years ago, whereas it certainly doesn't feel that long ago?