I assume most people generally have decent intentions and aren’t out there to spite people, except for shit-heel teenagers. I think your insecurities have allowed you to assume the worst because you think the worst of yourself, instead of what her true intentions were.
With such little information about what happened the logical conclusion I come to is she was being forward, perhaps as per her culture, while also being a little language-stunted. I’d put a small wager that she was either genuinely going to help you as she or someone she knows has had similar skin issues, or up-sell you on some type of cosmetic product they have. I’d bet on the former.
I don’t think it’s usual for anyone, especially staff of any establishment, to go out of their way to be intentionally nasty to people nearby. This has to be a monumental misunderstanding. The alternative is there is a lady going out of her way to tell customers they have bad skin to make them feel bad, and that just doesn’t ring true.