What kind of oral meds? If they were administering something like mineral oil for the impaction, that can be injected into a f/t feeder.
The swelling in the picture - is that right at her vent or is it further up? If at her vent did the vet check for impacted glands? One of my king snakes gets that periodically and the glands just need to be expressed (beware - the smell will run you out of the room!) and then she gets antibiotics afterward. The vet said it's just something that happens with certain individuals, though it's more common in colubrids than pythons.