Formula Milk

As of the moment po 2 oz every 2hrs (as recommended by her pedia pagka 1 week ni baby) po ang pagbigay ko ng gatas kay baby na 17days old. Kahapon lang po nakaubos siya ng 3 oz. Tanong ko po as a first time mom, kelan po need mag add ng ounce of milk? Like 3 oz na every 2-3 hrs