I hope it isn't silly to double check this with Reddit, but the other day I was walking down my stairs and I could see light coming from under the door to my dad's room. 

"Oh, he's still up, cool" I thought as I opened it, only to find that it was dark and empty inside

I have found this hard to get off my mind since it sticks out to me like a sore thumb. The idea that I am developing something psychotic is giving me a lot of anxiety.