[Thin Lizzy]

Sorry to read Lola's got a lump, it's important when you phone the vet on Monday that you ask for an emergency appointment, most vets reserve a certain time each day that deals with emergencies, the sooner you see a vet, the quicker you get a diagnosis.
That carrier is fine, just be sure to pack it with plenty substrate and toilet tissue. I would include something from her cage like a hideout/house, having her being able to smell her scent will be a comfort to her and a piece of apple or cucumber.