What Is Causing The Sharp Pains In The Wounded Area Of My Hand?

hi, i fell on the concrete and got a deep bruise on my left arm,under the elbow. I covered it almost immediately to stop the bleeding but didnt apply ointment and sterile pad until the next night and i got a bacterial infection. This is the forth day since my accident and i started antibiotic treatment 2 days ago. i still feel sore, although the wound is getting cleaner, however i feel sharp pains that come in form of shocks all of a sudden around the wound surface, about every 15 minutes and it is really uncomfortable. I feel like removing my bandage and sterile pad but i dont want to expose my wound. Do you know what is causing these shocks? I am 6 foot 3, 34 yrs old and dont have any other health problems