What Causes Red Sore On Penis After Using Warticon?

I finished treatment with warticon about 3 days ago (i.e. 3 days ago was the last of the 7 day treatment, so have now gone 7 days without application) and have been left with a red sore with a strange almost yellow looking bumpy area on top. It is possible that this area was healthy, as the area I was actually treating was sort of opposite this site, and would have made contact when the foreskin was in its normal position. Is this normal? How long will it take to clear?