Oops, it doesn't look like 'symbol could one day' is a national day..

Other days

Emoji Day

nail polish

Nail Polish Day

first love

First Love Day

comfy

Comfy Day

one

One Day

boba

Boba Day

self care

Self Care Day

chocolate milkshake

Chocolate Milkshake Day

eat what you want

Eat What You Want Day

ponytail

Ponytail Day