I now that state of mind and for me usually it is depression lite. Doesn't have to be though. I had the great luck to experience "normal" like a month ago for a few weeks and it was nothing like being bored and not interested. I was feeling fine and calm and at peace and still interested in stuff. So if it were me writing those lines it would mean i am slightly depressed because i am a very vivid person. could be different for anyone though.