I don't post here and this account is fresh but I figured this might help people. Copy pasting my post from reddit below
1. Cardio. Make sure you're putting enough effort in to breath deep but not be winded after a minute. I usually run but ellipticals are probably better
2. Meditation
3. Using techniques from meditation/CBT/ACT to stand in frigid showers and breathe slowly and deeply for 30 breaths. I then turn around so the water is on my back for another 30 breaths. I'm usually fine standing in the water after like 2-3 breaths, it's not that bad
4. Maybe helped: lamictal+SNRI
5. Doubt helped but I took 900mg gabapentin today
Real life is fucking weird, like I woke up and the world isn't just a fuzzy abstract representation of itself. Ima go smoke weed now and probably ruin my progress. I'm also holding a guitar and am just amazed that this is my guitar that I bought, before it just kind of existed and that's it.
Edit: also magnesium supplements helped a lot. High absorption/glycinate is important, citrate is a laxative. I take 400mg in the morning and 400mg at night
Edit again: it's back lol. I have a working hypothesis that anxiety or whatever is resulting in subconscious hyperventilation (I do breathe shallowly) and the gabapentin may have relaxed me enough combined with the cardio. I don't know, hopefully it goes away again soon
IMPORTANT EDIT: once again copy pasting my reddit post
Another edit: repeated the process from when I briefly recovered. Definitely helped a lot but not 100% back today