Morning 😊, woke up thinking about you. Glad you got a little rest, worth reflecting on the fact you made it through again. Even in the midst of it you can remind yourself it is absolutely always a temporary experience, a horrible one, but always one you come out of. You may go through it again the next day but there's always a moment between & it helped me to remember that.
Hopefully you're having a nap now. For me (and it's always 'for me' cos we all experience this slightly differently) naps during the day don't come with the same jolting panic. Obviously that's not sustainable but worth letting yourself when it's bad like this.
There have been some really good suggestions here, it's worth bearing in mind these are all most effective if you can start them when your mind starts to kick off.
By the time I was fully in the fear & panic stage (shaking, faint etc) I had to take a diazepam, it was the only thing that worked at that point. Didn't use them otherwise, purely for that moment on recommendation from an emergency GP. Yeah. I ended up at A&E dead certain I was about to die lol. Like, I was in the car trying to tell DH I wasn't going to make it there but couldn't speak properly.
So things to do -
Cut out caffeinated coffee if that's a thing for you. Not necessarily forever but for the time being. Tea is OK cos the caffeine is absorbed differently.
Make a note of your absolute comforts. TV show, YouTube channel, food, blanket, smells. Anything at all.
Someone mentioned a cbd vape pen - that's not a bad idea at all. It forces calm breathing. There's nothing in there that will hurt you - the excipients are the same thing as is in theatrical fog.
Find your mindless game. It wants to be something with no timed targets & doesn't require you to think - no puzzle element. Something you can play on autopilot & can put down (fall asleep) any time & it won't affect the game. It wants to be engaging & cute. Ideally you get sleepy while playing & can let the phone just fall out of your hand as you drift off.
Get a 1000 piece jigsaw (I love the Colin Thompson ones). It's super benign & no pressure but requires your focus. If you're short on space, trying doing it on the floor under a rug so you can just pop the rug back over & it's secure.
Breathe in your diaphragm - so your stomach is rising & falling rather than your chest. In through your nose & out thru your mouth. At first don't make them too long as you can feel dizzy & that just makes everything worse.
Speak to your GP today. Be absolutely honest. Let them help you. Don't put off starting what they give you like I did. It will likely be sertraline at 50mg which is a very low dose (I'm still on that & it works for me).
For the first little while (maybe 4 weeks) you might get physical symptoms but it won't make the panic worse, it might just feel unchanged. It's common to lose your appetite, struggle to sleep &, if you're me, get uncontrollable diarrhea a couple of hours after the first tablet.
If you're REALLY lucky, that will happen whilst you're standing outside talking to your father-in-law.
If you're really REALLY lucky, you'll have eaten Chinese the night before with loads of red food colouring in & your poop will look like blood & you'll ABSOLUTELY think you're dying & be on the phone to your GP sobbing 🤣.
Thing to remember is it's all temporary & none of it is worse than what you went through last night. It's more irritating & inconvenient.
GP might want to do bloods to check anaemia, thyroid etc too. All stuff that can make it worse & easy to help with/rule out.
Yes, this is long but from experience I know that helps too. It's all about acknowledging what is happening to you then absolute distraction.
You aren't alone, you're not weird, you're not dying & you do ALWAYS come out of it.