I'm not surprised that are similarities with other people on this board, the breathing thing is even worse the new orthostatic hypotension that I have.
But I'm getting better I've been doing a lot of reading about the possible autoimmune causes, and it looks like orthostatic hypotension and postural orthostatic tachycardia syndrome can often be from autoimmune.
And the gut is responsible for all of it most of the time I was eating a lot of refined Foods refined sugar crap like that for a long time but I gave it all up . I even gave up Dairy and gluten giving those up help tremendously throughout the years but it wasn't until the zinc carnosine that I've made improvements and got rid of the breathing thing apparently, but I can't go and start eating crap again because it'll trigger flare-ups autoimmune flare-ups so take that on board if you get better don't go back to your old ways and do stuff that'll trigger flare-ups.
The brand I buy is called Doctor's Best PepZin GI, Zinc-L-Carnosine Complex,
https://www.amazon.com/dp/B0035BYOSA/ref=asc_df_B0035BYOSA5750070?tag=shopz0d-20&ascsubtag=shopzilla_mp_1041-20%3B15504599169114557024810070302008005&creative=395261&creativeASIN=B0035BYOSA&linkCode=asn&th=1
I was reading through all the reviews they had to see what other people are saying abou.t it seems to work quite well for Digestive issues, it can chelate copper out of your body if you take a lot of it but the dosage that help Probably won't be a problem. I don't supplement with copper I just eat a really healthy diet and Foods that have copper and that kind of thing anyway good luck.