What Causes Chronic Dull Ache In Shoulder Blade And Between Breasts?

I HAVE HAD A DULL CHRONIC ACHE IN MY LOWER RIGHT SHOULDER BLADE AS WELL AS BETWEEN MY BREASTS ON MY RIGHT SIDE THAT FEELS LIKE A SPHERE GOING STRAIGHT THROUGH. MY RIGHT ARM IS TINGLY AND I GET CRAMPS IN MY RIGHT SIDE UNDER MY BREAST AND IN MY LOWER RIGHT SHOULDER BLADE. MY CAROTID ARTERY ON RIGHT SIDE SEEMS TO BE THROBBING CONSTANTLY.