When my twins had their surgeries in December, one of them vomited 2 days postop and it lasted a day or two. The docs said it was probably one of the pain meds and it would wear off and it did. Plus, she was taking quite a bit of milk and wasn’t really active as usual. We did have some diarrhea afterwards while still in hospital, but they said that was the leftover bowel prep.  I would keep an eye on her and if it lasts much longer, I would call my endo or pediatrician--the surgery effects shouldn’t last that long.