Ever have a Meh kind of day?

I'm not sure if it's anything specific but I'm just feeling Meh today. It's a warm September day, everything is still green and sunny and beautiful but I'm sitting in my dark bedroom, trying to avoid anything adultish. I could be reading the ton of books on my TBR (to be read) list, and should be doing edits on my manuscript. Heck I could even be preparing all the ingredients for salsa, but I really just want to do nothing... See, Meh.