I was sitting in front of my computer and suddenly the screen got darker and darker, and then the whole room got darker and darker till I couldn't see anything. It was completely darkness. I screamed but couldn't hear my own voice. I couldn't move either. Then somehow I realized I was dreaming(for the first time I knew it when I was dreaming, so weird

), so I tried to wake myself up. When I screamed harder, I woke up and found myself screaming in bed.
I still can't forget about this. Is it sleep paralysis?