Since around 3-4 months I have had a sensation of pins and needles on my left shoulder blade all the way up to my shoulder. If I am sitting without support only then I would experience. Nothing while lying down. Four days back got back massage and am doing a little stretching. It feel relaxing but now there is a little throbbing pain around shoulder blade, shoulder and arm. There is no pain on the spine or neck and no redness anywhere on the back. Pls guide.