Having a little sleeping problem now

Gim Yong once told me that if we don't sleep enough, we'll incur a sleep debt.

So probably that was why I became a hardcore sleeper in year 1 and 2. I would sleep anywhere. First, it began in class when the lecturer was talking about thermodynamics. Then I would skip classes to sleep in my hall. Sometimes I sleep so much that I would forget the meals.

Now to think of it, I slept through most movies I watched with my ex. But probably that's because we had a tendency to watch boring movies.

And at night, I would have no problem falling asleep even though I sleep that much. That's about erm... 10 to 18 hours of sleep time everyday???

Then in year 3 and 4, I suddenly find that I'm not able to sleep that much. I would wake in the middle of the night or I'll not sleep for one whole day. Is that because I used up my sleep??? hahaha....

Might be a good thing though