tretinoin causes initial thinning due to increased skin turnover frequency, underlying wrinkles might get more noticeable but its supposed to thicken that thin skin more in the long term.
That's interesting, but not surprising. There has been a lot of negativity around retinoids causing 'thinning skin' over the years, and it's definitely not something to worry about.
I'm not using it everyday, just 3 times a week. I want to make sure I use the best, most effective and strongest stuff
Just make sure you are watching out for peeling, sensitivity and redness. You have to monitor your skin, and make sure that you are training your skin to behave, not torturing your skin to behave.