Is Retin-A being used right if it doesn't cause peeling or dryness?

My doctor prescribed me Isotrex 0.05; I use it every third evening, & apply it approximately 20-30 minutes after I've washed my face. I use a pea-size amount which is enough to cover my entire face. However, I've noticed no dryness or peeling. Is it still working the way it should? I'm using it to treat blackheads, whiteheads, as well as wrinkles. Otherwise, my skin is normal, I don't have severe acne. Any advice would be greatly appreciated. :)