What could help me show my teeth when I smile? (photos)

I haven't been able to smile with with my teeth since before I can remember. I have never has braces or a retainer, just routine dental check ups. I'm don't sure if my nose is too big or my lip is too long or my teeth are too short or a combination. My smile also feels and looks very forced, I feel as if it's always behind a curtain.

No doctor answers yet