Sounds like your going through a tough time! You sound really self aware, generally what people fear is the panic itself, rather than a specific fear, but not everybody realises that kwim? And major congrats in coming on here and asking for help!
There are a couple things you can do, first of all, are there times of the day or night when you don't feel panicky? What makes those times different? Are there specific triggers or is it just out of the blue? If you can figure out what triggers it, then your in a much better position to work around it. Secondly, never underestimate the power of 10 deep breaths! There's also just going with it, just tell yourself 'ok I'm panicky, that's fine, I'll wait it out' rather than fighting against it. Trying to decrease a thought or a feeling never really works, it's like not thinking of pink elephants
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