Right upper shin, to right of bone, in the muscle. Sharp localized, but I wouldn t say stabbing, pain when I press it onto the floor as I move from a sitting position to standing back up again. That s the only time it hurts. It goes away as soon as I take pressure off it, dissipating and completely gone within moments, but the sensitivity to the area remains for hours after. No marks, no redness, swelling or heat. No known injuries or overworking of the area. My job has me on the floor for an hour at a time, playing with a child, then I m up, driving, walking, to my next appointment. Several 1-hour sessions in a week.