I had a similar issue a few months back. It started in my right shoulder blade, then to btwn my shoulders and finally up into my neck and and boy did it hurt!! The whole thing was one big knot and it hurt even to barely touch it. About the time I was ready to go to the Dr, it finally, slowly went away. I credit mine to lifting too much overhead on the barbell. I took a lot of hot, hot water pounding showers, heating pads, Aleve, and deep, hard massages from DH that hurt like crazy when he did it, but felt so much better afterwards. I also got a foam roller, which once I figure out how to roll my back without gettin my hair stuck, really helped. I also found that holding heavy wts, and letting them pull the muscles down (at my sides for my neck, and in a one arm row position for my back) for short periods of time, helped to stretch things out. It probably took a month or so for it to completely go away. I believe Kathyrn had also posted me a few good suggestions. If it doesn't clear soon, you need to go to the Dr, there may be something truly wrong. I'd go with heat, Aleve/Advil, massage, heat. In that order. The massage may hurt like crazy, so I'd take the Aleve 1st. If it doesn't clear up, call the DR, better safe than sorry. Good luck, and I hope you're feeling better soon.
Nan