hi Poppy - I cant help with the neuro in NZ or Aus as Im in the UK but I too have gluten ataxia. Many of your symptoms sound like ataxia - migraine is a symptom related to gluten; as is fatigue and the unco-ordination/balance as the cerebellum is affected and this is the balance centre in the brain, Im told that swallowing can be affected and tremor seems to be an ataxia symptom. For me being jumpy - is that what you mean by 'startle at nothing'? I was like that. I also had peripheral neuropathy which can cause numbness.
The good news is that most of my symptoms are majorly improved now after 3 years of being gluten free. Ive found that i need to be very strict - so dont have foods that say 'may contain traces of gluten or cereals' as this is too big a risk for me to want to take - the antibodies caused by eating gluten stay in your system for months and cause problems! Many of the symptoms may be caused by vitamin/mineral deficiiencies - which may be the cause of the numbness for example. The cerebellum is attacked (not sure how this works!) and this causes the problems of balance and concentration.
My 'top tips' are:
Be kind to yourself and accept that at the moment you get tired more easily so get enough sleep!
Take a good vitamin and mineral complex (gluten free of course) and fish oils as well if you can! get your B12 and vitamin E and iron levels tested as these are common deficiencies in GA I understand
Read what Dr/Prof Marios Hadjivassilliou (Sheffield) has written about gluten ataxia
Read labels of everything - gluten is in so many things that you wouldnt imagine - pate, potato crisps, soups, baked beans, gravy powder and sauce mixes, etc as well as the obvious cakes, bread and biscuits
Coeliac websites such as coeliac UK offer some useful info but I dont think they are strict enough for those of us with GA
Ask in restaurents whether foods are cooked in the same oil as gluten containing products - I have found they tell you (and think its correct) that their chips or onion bhajis, for example are gluten free, but iff you question them you find they use the same oil to cook battered fish or onion rings - which contamiinates the oil and means it isnt gluten free - tell them you have to be really careful or it will make you ill - i think they have visions of you throwing up ha ha!!
gluten free oats are supposed to be ok but I avoid them as I think they give me symptoms - some people avoid other grains too and there is a good website with a lot of info on this called www.trulyglutenfree.co.uk
Your symptoms will improve Im sure if you are strict with the diet and I have found that there are GF alternatives ffor most foods, though sometimes you have to make them yourself, so if you cant cook you need to learn!!
hope that helps, please ask if I can help with anything and you can message me privately if you would find that helpful,