Suggest Treatment For Shoulder Cuff Pain

After I had a case of shoulder cuff pain, I dis the exercises recommended and a short time later, I began to have rather intensive pain across the whole upper back, with shots of pain extending up to me left ear an up the left part of my head. This pain would last about a week or so, then things got better and right now I am esperiencing the pain across my shoulders and a pain going from the left shoulder, traveling up through the skull half way to the crown. An hour of rest on my back seemed to,alleviate pain enough that I could prepare a simple dinner - but now the pain has returned behind the lower ear. I have arthritis but I don t know how severely it is. I am in good health otherwise (as I am 82) and I want to keep healthy! What suggestions might you have? Thank you for your time.