I'm 18, the moment I turned 17 my mindset literally shifted and my frontal lobe started to ACTUALLY develop.
It's a weird feeling, it's like everything you were ever curious about and the things you didn't understand just click into place, but then that can also be room for depression, because sometimes you need to accept the fucked up reality of shit, as depressing as it is.
Though that being said, yk the inner monologue trope from tween shows? I've had that ever since I was a kid and I like to imagine that even as I get older I still have the quirky part of myself following me around.