I've had this happen to me too. I took a late afternoon nap (still daylight) and woke up a couple of hours later (pitch dark). When I woke up, I looked around and couldn't figure out if it was early morning or what. I was fully clothed too. Confused to the max for a few minutes.Having a day here. Had a bit of a headache, so went to lay down. Fell deep asleep again. Woke up, thought it was morning. Took a shower and everything.
Then looked at clock and wondered why it was still so dark at 8:00. Because it is 8 PM!!! I am a nitwit to the highest order.