Hi mommy
Gia should have been given fluids during her spay. It is perfectly normal to not poo poo for a couple days after the spay. Is she drinking or eating at all? If not, you can use a little syringe to give her small amounts of water until she feels up to drinking on her own. If she seems dehydrated (gums should be pink and not sticky) or you are concerned in any way, you should give your vet a call and see what they recommend.
Also, are you positive she hasn't pee peed? Has she been with you the whole time she's been home since yesterday? Sometimes they will sneak in a pee pee when you are not looking