My left hand side is in severe pain. Earlier I had surgery and was put on a drip. Next day some medicine was to be injected through the canola iv but nurse found the drip flow stop so she banged/ tap very hard on the canola and then injected medicine fast. This causes the pain and it's now 3 months but did not disappear. Pain grew unbearable and spread till fingers and swollen slightly. I tried different ointment but no effect. I think it's nerve. Advice test and medicine.