Hi, Lauren. "The torch was a give-away to your accent"
My concern for Mango is that she needs the antibiotics to insure there is no residual infection associated with the surgery. Is she able to keep any of the antibiotics down? If it isn't the pain meds, then like human, she could be sensetive to the antibiotic. What is she taking? Clavamox? I would definitely revist the vet via phone ($$), and find an alternative. As you know, her surgery is equivalent to a hysterectomy and no one has major surgery with preventative medication.
Make sure she doesn't become too frisky and try to nap when she does. Warmly, Deborah PS At least a human can say "oh, that hurts" or I don't like the place, Momma. That is the reason that I carry my pets into the vet's office. The drive over seems to set off the alert initially.