I haven’t got mine yet, but I did saw post that some people have breakout after introduced this ampoule into their routine.
if I were you, when I want to test new product, I will do patch test for at least 3 days(non active product) and longer period for active product to ensure my skin would not react badly to the product before I apply on whole face.
I will also minimise my routine to as simple as I can, as I really would want to see how my skin reacts to the new product, it would only comprised of cleanser, soothing/calming toner that I usually use, new product (ie the ampoule), basic moisturiser that I usually use.
I also suggest you to temporary stop using your current serum when you’re testing out this ampoule as ampoule is much nutrient rich than serum and some skin might not tolerate an ampoule when ampoule is first introduced into their routine.