Write down details names dates, contact numbers etc, whenever you have contact with any medical professional. Keep notes of discussions and educate yourself via the internet so you know what questions to ask. There's probably an on-line support group for your condition out there somewhere too, could be useful. If you don't already have one, get a good GP. Ask around, it's important to have a good open relationship with this person
A friend was recently diagnosed with sarcoidosis and helping him deal with the local DHB has been an eye opener. After telling him he had a 90% chance it was cancer, they finally diagnosed it correctly four weeks after he was first admitted. Now he's getting his notes lost by various specialists, check-ups repeatedly cancelled with no notice, calls not returned, and a complete lack of any coordination between the various hospital departments. Thankfully his GP is going in to bat against the DHB in order to get some action.
Good luck anyways