Employee was moving a jack hammer at 3:00 a.m. then a bottle of water at 4:00 a.m. After 4:00 a.m., he felt a sore area and sensitivity around his belly button. Employee finished shift and was off for the next two days (incident happened on Monday in the AM, employee returned to work on Thursday at 8:00 a.m. EE's wife brought in doctor's note on Thursday at 11:30 a.m.