Last night, something weird happened…

At about 10:40pm, I closed my eyes and tried to sleep. I was thinking about stuff, and I started thinking about a certain topic. While thinking about that topic, I decided to open my eyes, and see what happened. I opened my eyes, and looked at the clock, it was 2:15 am.

I was thinking 'wha???' as I hadn't thought I fell asleep. It didn't feel like 3 1/2 hours tho. It was odd.

Any explanations?