Ice it. Ice your injury for 20 to 30 minutes every 3 to 4 hours to reduce pain and swelling. Continue this for 2 or 3 days, or until the pain is gone. Compress your leg. Use an elastic bandage around the lower leg and ankle to keep down swelling.
Finally, two terms you may run across in the future are oxidizing agent (or oxidant) and a reducing agent (reductant). An oxidizing agent causes oxidation and is reduced in the reaction. A reducing agent causes the reduction in the redox reaction. The reducing agent is oxidized in the reaction.
Reducing agent. The oxygen (O2) is being reduced, so it is the oxidizing agent. The glucose (C6H12O6) is being oxidized, so it is the reducing agent. In organic chemistry, reduction more specifically refers to the addition of hydrogen to a molecule, though the aforementioned definition still applies.