Amanda,
My thoughts are just that, my thoughts.
Most importantly, please do not let anything act to create an atmosphere of conflict between your father and the family. It is time to provide support for dad, as he deals with the diagnosis and treatment.
That said, it took more than 3 weeks from my initial diagnosis until anything else happened, including the follow-up tests, scans, and initial biopsy. The real question, then, is, "Have appointments been ACTUALLY BEEN SCHEDULED for further testing in 3 weeks time? If yes, then the doctor is already moving things ahead (a bit faster than mine did).
Caught early, bladder cancer can be very treatable. But do not expect expect things to happen quickly. Once diagnosed, many here have expressed concern about how slowly things happen. Constantly waiting for action, and worrying while waiting, is perhaps the worst part of a BC diagnosis. Eventually we get used to the snail's pace of treatment.
After my diagnosis, I was in no shape to even think about a trip or other adventure. Your dad is doing far better than I at remaining calm, that is good for him. I'm sure you would like to quiz the doctor about what dad is telling you, and that is not likely to be an option.
Last thought - IF there is a schedule for follow up in 3 weeks time, everything could be good. Give dad a big hug.
Best,
Jack