I can't add much more--my first few days were awful.
For the feeling of not being able to even sit in my own skin, I took my dog on as long of a walk as I could stand. Sometimes that was a half-hour. Sometimes it was 5 minutes. But I was moving--and honestly broke it down inside my brain into: "One foot after the other".
It certainly didn't "cure" anything--but for those few minutes my focus was on one foot after the other rather than the anxiety of what my body was going through.
Water, lots of water.
I am sure it is hard to think this way because of the mental/physical war your body is fighting with itself--but the decision to not drink is the best thing you can do for it--and for everyone who loves you. Take care, and lean on SR for what ever comfort you find here. I know I did, and do.
Best, and thinking of you.