The only case that "springs" in my memory - is GBS - on occasions GBS can cause "autonomic" dysfunction and not only motor dysfunction.
you need to get to neurologist and discuss this case in addition to neurological exam - you may benefit from IVIG.
There was a medicine in USA called propulsid - it may still be available in Canada or Europe - it may help out.........
Do the nerves ever recover?
it really depends on the degree of damage, unfortunately, there is not objective way to evaluate it. Peripheral nerves may recover, but at the slow rate - about 1inch per month, autonomic nerves are different and I do not want you to have unrealistic expectations.....
if you look at GBS in general - if it recovers fully - it would take anywhere between 1 month to 1 year, after that the condition becomes CIDP (chronic) - and treated with above mentioned infusions.