In my own life, I've noticed that time seems to fly when I have a "real job." When I'm not working a traditional 9-5, time goes much slower and it seems like I get a lot more satisfaction and fulfillment from each day.
A good way to gauge this is to ask yourself, "How far away is Christmas?"
When you're a kid, if your family celebrates Christmas, that's probably one of the highlights of your year. In January, it seems forever away. But even in November, you'd ask your mom every day, "How many days until Christmas?" And she'd say "Only thirty more days", and you'd groan. Thirty? That's so far away!
But as an adult, Christmas never seems that far away. By fall, it feels like Christmas is just around the corner. With twenty days to go, you start to panic about whether you'll have enough time to buy gifts and make preparations.
When I'm not working a "real job", Christmas still seems pretty far away. Even in November.