self-diagnosis is pretty clear

  I've been having muscle soreness in one specific spot of my back for the last few days.  I've been shoveling a lot, but where I usually get pain from shoveling is wrist and thumb areas, not my back, and this isn't in the part of the back that people would expect to be shovel-related.  I spent quite a while last night lying on a heating pad (you're not supposed to do that), turned it off, went to sleep, and woke up without the soreness.  After an hour of sitting at the computer, it's back.  I had guessed that it was caused by my posture and now I'm pretty sure,  Slouching in a bus seat reading can't help, and during the messy weather, the bus trip to and from Alewife has taken almost double the usual time.  My posture is one of my life projects, but clearly I need to step it up.