What you need is a diagnosis. No one can cure something without knowing what is wrong with your shoulder. Diagnosis involved Clinical examination and/or investigations. So meet an orthopedic surgeon. Get a diagnosis. Then decide what needs to be done.

Gentle Shoulder Stretching. Core Strengthening Exercises. Gentle Neck Exercises. Avoid sleeping on affected side. Warm up and cool down is a must. Contrast bath---It is a form of treatment shoulder is applied warm water followed by the immediate application of the shoulder with ice water. This procedure is repeated several times, alternating hot and cold. Note that the treatment should always end in the ice water, as heat will induce the body's inflammatory response, while cold helps to decrease inflammation.