I'm sure little Coco will recover in no time at all. My 14 yr old Jennie got spayed when she was ten (years). She had developed pyometra and besides had breast tumors. She had three teasts amputated, and also had some teeth pulled out. Well, she was in a lot of pain, NOT FOR BEING SPAYED, stay calm, but for having had the breasts amputated which involved the cutting out of a lot of adjacent tissue, skin and muscle.
Despite this double surgery and not being especially young, Jennie pulled through in a couple of days, esp. when the pain from the removed tissue worn off. I guess the vet will give you some guidelines to follow after the surgery but as long as she does not pull the stitches off and the wound looks good I'm sure Coco will be fine.

Rubi and

Jennie.