I'm experiencing tingling located at my left shoulder blade area, which leads to severe but temporary pain. I've felt the skin around the area and I noticed my skin is completely numb.

I've had this condition for several years now, but it definitely wasn't as bad as it is now. I play piano (quite a bit) and I often play computer games as well. I'm thinking the position of having my arms extended in piano and games is affecting this...

I can barely carry my backpack around in school now and it's barely 10 - 20 pounds.

The only relief I get from this is when I'm lying down or sleeping.

I'm wondering what this could be caused by (in more "Doctor" terms) and what I should do from here.

Thanks.