Lort Smith and RSPCA both tend to be far cheaper and are willing to work out payment plans. There is also a veterinary teaching hospital in Werribee which is much cheaper, someone else might know the details? I have a GF who has travelled from the Mornington Peninsula to Werribee for any surgery her two labs have required (one had a gynecological cancer and the other has had surgery on knees and hips) as it was the only way she could afford it. I think the surgery is performed by final year students under supervision. Might be worth investigating.

I hope it is just an infection and your girl is much improved this morning.