Skin Turned Deep Purple After Few Hours of 20% Salicylic Acid Peel. Is This Normal?

I had my first 20% chemical peel done today by my dermatologist.He said my skin responded pretty well to the peel. but then it started to get red and afer 3 hours now, it has turned deep purle in colour and tight like a leather. My doctor advised me to continue using "Stievamycin Gel" at night. Since I've applied it, my skin stings like crazy. I am worried is this deep purple burnt skin affect and the hot sensation normal? What should I do now?