Man, i feel ya. I would sometimes confuse my panic attacks with autistic meltdowns, so some of not all my advices might not work.
First, the obvious question ever(imho): are you on any antidepressants? My doc is pretty chill and she told me that it is very hard to achieve anything useful without meds when the condition is severe. Im currently on Wellbutrin 300mg and Lexapro 20mg, tho Im starting M-Duloxetine instead of lexapro tmrw, but cant say anything about those yet. I would say I found prozac fucking me up worser and lexapro not treating it all fully (with lexapro my condition went from severe to moderate which is smth). It very depends on a person tho what drugs will work (Pro tip: if you are in canada or usa, google those whih one covered by your insurance. For my Wellbutrin 300mg (not 150 tho) and M-Duloxetine are covered, but not lexapro.
So yeah, from my experience, pills will significantly help
Also, so fucking real with therapy

. It is very hard to find a good therapist, so partially changing to different therapist whos specialization is in panic attacks
And now "drink carrot juice part". Shit that i was shocked that worked for me when I can use it: salt on the tongue. If you feel like you are about to have one, just throw bunch of salt on your tongue and your mind will switch to that and focus on salt instead of fucking you up.
I dunno what country are you from, but I think some countries give you service pets for free if you are eligible (pretty sure you are). Having a service dawg can help you because its generally hard to use any grounding technics on your own (lmk if your therapist didnt share any grounding technics with you tho, im gladly will share my list) and those are trained to help you in such situations
More of a carrot juice: find your confort token you can carry with you. Ig it more of autistic part, but i have a stimming ring (that i can spin) and that one sh coping tool that can help you minimize the harm but still give you enough stimuls to "snap back", it is not as unhealthy as sh itself
Also, try find the triggers (they might be not as obvious if you feel like attacks are random, writing it down might help) cause "know your enemy" type shi. I know ill get overstimulated from noises and will freak out after, so i wear noise cancelling headphones and avoid loud places
Very cliche, but if you have friends/people you trust, you can tell them so they an help (for example with activities that you cant avoid but might trigger the panic attack. There are articles (i can send them if you cant find) on how to help a person on their start of panic attack (just tell them your boundaries like ask them to not touch you if you feel like it will make it worse)
And remember- healthcare is pain in the as, so try "eating an elephant by pieces" if you feel like my suggestions are to much at once (get pills, fill in forms for service animal... etc, etc) id suggest you to start with pills and slowly do whatever you feel could work
Good luck to you, traveler, i hope you will get better