ouch, that is not supposed to happen. stop using it. and put some ice on it. maybe take some benadryl. I hope it feels better!

I have the very same problem right now on my cheeks, chin and forehead! Could anyone let me know how long it takes for the red patches to clear up?

Definitely an allergic reaction or sensitivity issue. It will take a while to go down. You could try benadryl cream or something that does not contain steriods in it. Your skin is angry but given time, it will bounce back. In the meantime, no makeup or other active ingredients. Water only or water and a gentle cleanser such as cetaphyl or Cerave .

Stop using it since I think it's not really compatible with your skin.

It'snormal for benzoyl peroxide to burnor sting just a little bit when you apply it. Your skin may also get red and a little itchy. It's just typicalbenzoyl peroxideside effects, especially during the initial stages of treatment.
Truebenzoyl peroxide allergiesare very rare. For people who areallergic,benzoyl peroxidecan cause itching, swelling of lips, tongue, or throat, hives, and trouble breathing

This happens to me too - with both benzoyl peroxide and salicylic acid. My dermatologist told me to avoid both of them if it happens.