What Causes Burning Pain Under Shoulder Blade And Breasts?

I am 58 years old and a few weeks ago I started have stabing and burning pain under right shoulder blade the stabbing pain come and goes but the burn pain never goes away, also very sore to touch in the shoulder blade area. In the pass week I notice very tender places under my arm and side of breast now today my hold breast hurt and burns, I don't fell any lumps just sore place underarm and breast is sore. Been taken Ibuprofen for pain.