How early is too early?

My son is 3 years old recently i started trying to get him to learn things and he mixes things like calling a girl a “he” and i asked him what are you a boy or a girl and he laughs and says hes a girl n i tell him no you’re a boy and he’s like no im a girl and he takes it as a game but a little concerned now bc he always says when i ask him that he’s a girl or he says no im not a boy im Aiden . For instance when i paint my nails he tells me to paint his nails too or when i look in the mirror he copies my pose too. Im just a bit confused because this is my first kid.