This morning, I tested Lunas urine again and bilirubin was still increased, and so was protein. She's still acting "normal", though ...

Could the abnormal urine bilirubin have been a happenstance thing? Could it have been from the infection, or from the treatment? I'm saying big prayers for precious Luna and I have a candle for her on the Pet Talk gratefulness.org page.
I don't know, but according to the vet, it's unlikely ... Thanks for the candle, Elyse!