Was about 21 hrs late taking my first pill in the pack, how long should I use backup contraceptives?

Claudia

Was a dunce and completely forgot to pickup my new prescription before the new pack started. Got it today and took it about 21 hrs late. Took my second one shortly after at normal time. Usually they say use backup contraceptives for at least a week but I’m a bit more worried bc it’s the first pill. Does that make any difference? Thanks for the help!! xx