Sick Guinea pig

A couple of weeks ago I noticed that Babybelle had a lump under her chin, it grew quite large and I noticed that she wasn't eating properly so took her to the vet.
The vet said that the lump was an abscess and it needed draining.   Gallons of very smelly puss drained out and I was sent home with a bottle of antibiotics and £40 lighter.  Said that she needed to see her next week but she was not to eat for 4 hours before the appointment as she needed to see her teeth properly.
I went back today with a very sad, very hungry guinea pig.  Again she could not see her teeth properly and said that she needed to come in for the day, to be sedated to have the lump cleaned out properly and to investigate her teeth.  I have to take her back at 8.30 a.m. tomorrow morning...............