i realise with the stage that you are already at this may sound stupid, but i always seem to have blood in my urine when dipsticked and with a previous oz visa i had to have a sample sent through my gp (whilst living in sydney) before they would approve the visa. One thing that made a big difference was being well hydrated when i gave a sample. If i hadnt drunk enough i would always dip positive for blood. I have no idea why but they werent overly concerned.