Open Question: will a muscular pain will stay for more than a month?

I am in my elbow, left shoulder pain radiates to the left uppler (cuff muscles) sometimes. This is already in the past month. I use all kinds of pain killers () external factors. However, this is still persist. Times the least pain I have. But sometimes it interfere with typing on the computer I would like to work (I think some stiff left shoulder and upper arm). Can I have some suggestions? ? I started to diabetes. What I mean is 9 hours fasting 120mg/dl. At the same time this is the winter in Dubai, and now I live in place. In addition, I have some pain for the last three years doctors told arthritis Initially, I had a lot of playing volleyball, my bare feet left knee at an early age.