Hi Gavin,
i am so sorry and I feel your pain. I have a problem with the receptionists in the medical community 3 months later still don’t have a true diagnosis. What most people will never understand is how not breathing sets off anxiety like crazy !! They say smell a rose and blow out a candle. I’m sorry you don’t have an e tank, when I get anxious I set my e tank to 15 liters and use a non rebreather mask until I feel better and a fan works too I sleep with one. I wish you luck and hope it all gets managed soon!
Dee