Oh hey, that's a pretty interesting thing. I want to know something. You sometimes think you're a Korean girl and sometimes think that you're a Eest-European girl. But in fact you're white (European) or yellow (Asian). So, isn't it obvious when you're wrong? For example if a European girl look at the mirror and sees an Asian girl, couldn't she just realize that in fact she is wrong? And vice versa: if you're thinking you're a European but see in the mirror an Asian face, can't you understand that you're wrong?
Or at least when you see your ID card or passport something? Isn't it there clear who are you and to know that you're mistaken?
Tell me more how do you feel or how do you think in these moments. How do you deal with it too.