Hey Aussiegirl, welcome! I too started off with dreaded knee problems as a kid.
btw don't worry too much about the radiation from a CT of a small area. You get about the same amount of radiation from a return long-haul plane flight. It's still not too high. Maybe ask for a simple xray of your neck to start with instead - that's next to no radiation.
Hope we can be of some help for all your other questions.
Glad to have you here. smile