It’s the same thing as with a hat: if you’re uncomfortable it’ll show. Comfort is the only difference between “hat people” and everyone else.
Long hair, short hair, no hair; if you feel good people can tell, and you’ll ascribe those feelings to how you look.
I’m the opposite, the longer my hair gets the dirtier I feel, until I finally crop it short, or if I’m really wanting that “clean fresh start” feeling, shave it off entirely.
Anyway, lucky for you, you don’t have to get used to it! Just wait it out and you’ll be back to your old self before you know it.