Last year after flu shot my arm hurt where the injection was. last few mths it has gotten worse where i cant lift/rotate without pain. had clicking noises for a while, now just pain & limited movement mostly at night/cold. what could it be?

I am sorry to hear that but the flu shot and your shoulder pain are unrelated. Most people have sore deltoid area after the flu shot but chronic shoulder pain is not a known adverse effect. It seems you may have a rotator cuff injury (more common) or a different shoulder problem. You should see your doctor for advice. Conservative treatment with med and physical therapy will ease the pain.