How old is your dog? Orbifloxacin can cause a photosensitivity in animals that are sensitive to fluoroquinolones. It could be that your dog has a sensitivity and this is why her eyes are red. After 13 days, however, her belly should not be very enlarged. I would call and make an appointment with the vet who performed the surgery to make sure everything is OK. After 13 days she should really be pretty much back to herself and if this is not the case you really need to have it checked out. Granted, pyometra surgery is a bit more complicated than a routine spay but your dog should actually have appeared to be a bit sunken in after the removal of the uterus, she should not have a very enlarged belly and definitely not 13 days post surgery. Because this is connected to the surgery your vet should not charge you for the visit because it's still considered a post-surgical visit. Please post back and let us know what the vet said.
Ghilly