That is one of the side effects of Retin A. It makes the skin more sensitive to sun light (easier to get a sun burn).
and causes dryness, redness, tenderness, and swelling of the skin. These side effects lessen with time.
A girl I worked with did the Retin A treatment. It took her about 4 months before her skin stopped peeling and looking dry. Once it did though her skin was smooth and really pretty. To my knowledge she didn't use any cream she just let it peel and said she had a sunburn