Not necessarily, you may only feel pain when you use or try to use the muscle / tendon that is injured. The tendon may have many micro tears, due to overuse and unfortunately occurs more to those mature in age ! (sorry!)

Do you have trouble sleeping on that side ? Pain sleeping on the affected side indicates a RC tear (supraspinatus muscle, responsible for initial lifting of the arm up to the side). This muscle attaches on the arm (at the area where you complain of pain).

Tendinosis of the supraspinatus muscle is very common, there are exercises to help (called eccentric exercises) however they are aimed to cause an inflammatory effect (ie pain, swelling etc) but research and evidence shows that this is actually productive. It causes an increase in cell activity which actually aids recovery.

I was shown....and used this technique on a patient with severe OA recently. The exercises caused him slight pain but only while we did them. Within a week he could lift his arm and was pain free (in a community hospital in UK with daily PT).

I can't say that this is the same injury you have.....as it's almost impossible to diagnose injuries without doing a physical examination. Just thought you might be interested.