I did a workout at the gym yesterday and later in the afternoon pulled my back leaning over to change the sheets on the bed. I am usually very careful to hip hinge but i'm assuming I did something wrong. The muscles that are tight and sore are the ones you use when you sneeze...very much at the base of the spine...erector spinae? multifidus? I don't know if it's a flexion extension issue but I've done it a few times in the past couple of years. Any advice you could offer would be greatly appreciated.