I spend several hours yesterday evening, hunched over playing a video game. That didn't hurt, but hunching over to read while in the bathtub seemed to the the proverbial straw. Nothing bad, just a painful twist. Once I managed to get out of the tub, I took some Alieve, then went to bed. My back still hurts this morning, so I took more Alieve before coming to work. Hopefully it will unlock as the day goes on.