Does rotator cuff syndrome usually cause many symptoms?

Usually. This is due to a sprain or tear in the tendenous support of the shoulder. In the most common form, the pain varies but you will have trouble raising your hand above chest level, the position to go behind your back to scratch will hurt badly and twisting motions like opening a jar will be very painful. Nsaids can help but if persistent over several weeks, see your orthopod.