How long will it take for a chemical burn from a peeling solution with 30% aha and 2% bha to appear on your face. I am a 27 years old female and a dermatologist just recently told me that I should not use retinol 0.1% or chemical exfoliate such as aha or bha on my skin and that it is bad for my skin. My skin type is normal to dry. She also told me these are to be used only with a doctors prescription and not over the counter. Could please enlighten me over this.