Honestly, it sounds like you went into this situation without properly informing yourself. You’ve already made uninformed mistakes like this with bleaching your hair.
I understand your anxiety, but it kind of sounds like you owe the beautician an apology. I’d wait to see if it fades after those 3 or 4 days, and then reach out to her to send your regrets.
While that is sketchy, they really didn’t need to do all that. They’re lactic acid and glycolic acid products are genuinely excellent. There’s a reason they’re referred to as holy grail products.