Absolutely you can say, "I feel dignified."

I imagine myself getting dressed in a tuxedo, looking in the mirror, standing up straight, grasping my lapels and saying, "I feel dignified."

Absolutely you can say, "I feel dignified."

I imagine myself getting dressed in a tuxedo, looking in the mirror, standing up straight, grasping my lapels and saying, "I feel dignified." I'd be suggesting that my elegant, majestic, mannered appearance has imbued me with a sense of dignity matching my appearance.