I really don't have the experience to be taken credible but I think you probably could have fed her 2 last night. Looking at rodentpro.com large adult mice at listed as being 20-29 grams (retired breeders are larger). With that being said if she ate half of what she could handle then I'd don't see issue in feeding her tonight. Just start the days over tonight so feed her in 5 days or 7 if that what you choose.
Xavier