Not to laugh, but LOL. I love all kinds of movies still, teen movies included. Have you seen '17 Again'? It still cracks me up. Love Actually is part of my permanent Christmas collection. Taste in movies is just that.
Maybe I have a juvenile sense of humor, sometimes. It doesn't make me a kid. I just never lost that kid-like sense of fun. I can still see the humor & I still can get into the emotions. Not everyone gets that, but that's okay by me.
I looked 16 until I was almost 30. Consider it a good thing.
I am saying, accept that about yourself, your youthful appearance, taste.
They call it 'finding your way' in the world because it is about you finding your own way of being.
Immerse yourself in something to get yourself out of your own head. You have to be brave and try something maybe a little out of your comfort zone sometimes/all the time, if you want to grow, and grow up.
You sound capable & responsible. There is nothing wrong or backward about you. You have the perspective of 25 years of living, so in fact, you are not 15 at all. Feeling it is a feeling. But it isn't the only feeling.
I'd say, embrace who you are. You sound just fine to me...Now we just gotta get you to believe it too