How to Fade Redness on Cheek from RetinA Burn?

About a month ago I received a raised red dry patch of skin on my cheek (like a chemical burn) from overuse of Retin A. The spot has since healed and I moisturize it everyday. However, there is still lingering redness and it looks like I have a red triangle on my cheek. I switched to Differin Gel, but have not been putting it on that spot. Is this redness permanent? If not, how long will it take to fade? Is there anything I can do in order to help my skin color to return to normal? Thanks.