So.... you don't know if you broke i toff while changine the oil... ot is it just blew up under the hood?

I fyou are talking abotu the top part of the cap (with the little oil symbol on it), it's made of a birttle plastic that could break (I guess) if you over tintended the cap (however, doesn;t it click when you tighten it, though).
I don't know, just grap a pair of needle nose pliers and unscrew it out. Buy a billet aluminum one from Bat or many toher places for 20 bucks and call it a day.