Culture shock is your brain realizing the way you grew up was one option, not the only one.

Meeting a place that runs on different assumptions reveals that yours were assumptions rather than simply how things are. That is disorienting, because a great deal you took as given turns out to be one arrangement among many. The discomfort is the recognition happening, not something going wrong. What you grew up inside only becomes visible from outside it.

Take one thing your household treated as obvious and find out how somebody else’s handles it. Ask without deciding in advance which version is correct. Notice which of your habits are now choices you can make on purpose.