EE was installing fike canisters weighting 133-148lbs on 12-30-19. EE developed pain in back over the next 2 days reported injury on Jan 2, did not want medical evaluation until Jan 7. Dr sent EE back to work with regular duty due to pain subsiding. EE reported still painful on 1-24-2020 taken to Dr. and given work restrictions and scheduled for chiropractor visit.