arm pain

i have a painful R SHOULDER that radiates pain into the neck and down the arm to the finger tips the pain first starts in the shoulder sometimes it feels like a pinching this progresses into burning across the shoulder blade and neck I have had an MRI of my neck which shows early disc dessication and an ultrasound of my shoulder showing bursitis which I had an injection for which lasted approx a week although I still had neck pain and pinching in the shoulder although no burning tablets do nothing what is going on