Is it normal to have this experience?

A couple years back I was awake late at night watching YouTube, then everything went black almost like my computer turned off. I tried to turn it back on but I couldn't find my computer. I reached out in front of me and there was nothing there, no desk, no monitor. So I put my hands to my sides to get up from my chair and I found out that I was somehow sitting on my bed.
I thought this was just a weird dream so I went to bed, but when I woke up the next morning to check my history the video I was watching was in my YouTube history and by browser history.
I didn't eat or drink anything and I know I didn't fall asleep in my chair.