Woke up wrong-side of the drapes

I'm standing in an OR I don't recognize, but I'm not the one at the head of the bed — I'm the patient, and the anesthesiologist is someone I've never met, and they're humming a tune I almost know. The monitors beep in a rhythm that doesn't match my pulse, and the fluid in the IV bag is a soft green I've never seen. I wake up before the mask goes on, and the whole day feels off-kilter, like I lost an hour I never had. Just that, no meaning I can parse.