well if u give your body a good blasting down the gym , yes u will ahe after the gym , but it should not be painfull, u have proberbly pulley a muscle or pulled a tendon.
protein will not take the pain away, u want to take some nosades ( ibroprofen ) take the swelling down. take 4 x 200 mg a day .
other than that restm it stu, do u know what movement u were doing to make this happen ???
Were on the shoulder is the pain exactly . front , back on the side , in the joint ???
or could u be over training, are u a gym begginer or have u been going long.
Do u know much about it really, ( not taklin the piss there mate )
just tryin to find out whats what really. they always teach u about clients knowledge and history
Ben