Have you had your hemoglobin checked? A CBC complete blood count would tell you. That would be the shortness of breath. Or a thyroid level TSH or other.
Hello, I have the same problem, here are some advice to cope with it and hopefully eventually get rid of it.
1. Realise that it's psychological, maybe it was something physical at some point, but it isn't anymore. By feeding into it you strenghtened that neuropathway and your brain is fooling you to get that release again and again.
2. Srop giving into it, no matter how strong the urge might feel
3. Ebrace it, rather than fighting it, if you want something to stop really badly, it won't happen-> say to yourself that its ok to have that feeling, it will go away eventually
4. The problem might be worse when you are in stressy situatons or while being tired-> practice calm and steady (shallow) breathing, maybe with some slow exhales (this will undo some potential overbreahting beforehand) and whilest doing that keep in mind that you are content with the situation and that it is not a big deal.
5. The number of urges around the day will reduce over time and the less you think about it, the better it will become.
6. Avoid stressy situations, for me it were stressfull videogames which led to me giving into the urge unknowingly and therefore deepening the "addiction".
Also smoking had a negative impact on my progress because its a common trigger, since its exactly that neurological connection to the breathing area which is messed up and any disturbence can be a catalyst.
Anyways, I hope this will help you get better and give you back your inner peace!