First Peel - TCA 35% or Lower?

35% TCA (tricholoracetic acid) is a great superfical peel. It has just enough kick to it to clear many skin dyschromias (brown spots) and it will provide overall facial tightening which is great. However, it is generally not strong enough to eliminate say lower eyelid lines. For that one has to step up to Phenol 89%. The peel can be comfortably performed in a office setting under local anesthesia.
Recovery takes about a week where you need to hide out but the skin never goes raw. If you follow your doctor's instructions to the letter you will be ready for make up in about 6-7 days. Unfortunately there is a huge difference between TCA 35% and TCA 25%.
With 25% you will see improved skin tone but much less clearance of the sun damage and very little lasting facial tightening. We call this more of a facial firmer. The down time is almost non existent. You will look like you have a bad sun burn for a few days.
Doing two 25% TCA peels is nothing like doing a single 35% peel. Do not let anyone but a very experinced physician chemical peeler perform these types of peels.
Also the Retinol product you are using is no substitute for preparing the skin with Retinoic acid (Retin A). They are not the same thing. Retin A requires a doctor's prescriiption.

For a first time peel, I would think about using glycolic acid or a TCA peel of 20%. Depending on your response, you can always go stronger. The goal would be a series of peels, each peel stronger than the previous. More importantly is to have the right medical clinic applying your peel that has experience and great knowledge of the skin, e.g. a dermatologist's office.

I would start at 35% TCA peel. But if you are unsure, then use 25% or even 20%. Go to 3 evaluations from expert skin peeling doctors. Regards.