Hi there. There are various possibilities for these symptoms of shoulder pain and numbness right arm like nerve root compression due to degenerative disc disease of the cervical spine compressing the nerve roots exiting from the neural foramina. Cervical spondylosis, bony spurs irritating the brachial plexus as it passes through the axilla. Trauma, frozen shoulder also could contribute to the symptoms. you need to consult an orthopaedician or a neurologist to examine you and do certain imaging like MRI spine, nerve conduction velocity studies to check if there is nerve compression, x-ray of the shoulder joint to check for any fracture, trauma etc. Muscle pull or excessive muscle strain in shoulder, vigorous exercise and weight training could also cause these symptoms. Hope this helps. Take care.
A number of possibilities occur, generally involving problems with the neck and its bone structure, musculature, and nerves. For example, nerve compression in the neck due to neck trauma, cervical disk problems, or nerve root problems could cause the pain and numbness you're describing. But without a proper workup it's impossible to say. I suggest you have this looked at by your doctor, and/or a neurologist.