Talk to Neuro Physician on Muscular Pain

About two years ago some area under my shoulder on the backside turned into blackish brown colour, I thought it might be because of continues use of that shoulder area and will get better with time. But now the situation is getting worse, the color is still same in that area, and before I never felt pain there but now from last few months I feel pain and specially when I do some physical work, and in winter it gets worse. Sometimes I feel like ants are crawling in that area. I will really appreciate if some doctor can suggest the appropriate treatment. I went to the physician here and he said it’s muscular pain, and advise me to take painkiller when I feel it. I want some permanent solution. Thank you.