My mother's heartbeat suddenly increases and she is also feeling some heaviness around her chest area. Actually, her heamoglobin was 6 around one month ago and doctor advised her 7 cycles of 300mg iron injections (3 ENCIFER or OROFER S) in 200ml normal saline.Since then, she has had five injection cycles in hospital. The last four iron injection cycles took around 2 to 2.5 hrs per cycle but fifth injection cycle was completed in approximately one hour by nurse . Also at the time of fifth injection, the canola was fixed on her wrist (since both the hands were painining as they were used for the last four cycles) and she was also told by nurse to hold the canola so that the same could not come out( but it was not the case in the last four cycles in which the canolas were fixed on hands i.e. on back side of palm). Since the application of fifth injection cycle, she was feeling heaviness in chest and her heatbeat suddenly increases. can iron injection be the reason for this?