EE reported to the maintenance office with alleged shoulder pain 3-20-13, claiming it was from the previous day 3-19-13 while inserting clips into a conveyer belt. Stated that he did not feel any pain on 3-19-13 but his shoulder was sore upon waking up the morning of 3-20-13. He was evaluated by a Physician on 3-20-13 and given restrictions and returned to work.