Tricks to slow down persistent panic attacks?

It’s getting really bad, and I don’t know what’s wrong with me. I’ve been having so many panic attacks, seemingly with no cause. I’m just paralyzed by the fear that I’m going to have another one, and I can’t even leave the house. The physical sensations that come with panic attacks have been worsening, and becoming more debilitating. I feel like my main problem is that I immediately lose all hope when I feel even an inkling of panic. Then I have no way of stopping it. And once I get to a certain point, there’s literally no way to stop it. The panic lasts for hours, until I get so exhausted I can’t keep going. Breathing slow doesn’t help, and it feels like no relaxation technique helps me. I don’t know if I’m doing this to myself, like I don’t want it to help. That’s really messing with me, I feel like I’m doing it to be manipulative. It just seems like the panic attacks come one after the other. It’s hard to sleep, I keep waking up feeling nauseous and dizzy. I can’t really eat, and I just can’t stop spiraling my thoughts, thinking that’s it really never going to get better. Basically, anything anyone could recommend to help would be great. Im just feeling hopeless, and I was thinking maybe someone had a trick to slow everything down.

Start here:

Sounds to me like your window of tolerance is so closed you have no room to do anything but move from one problem to the next. You need to stop that cycle by figuring out whats causing your stress and working on reducing it. That's the biggest thing you can do to start reducing frequency.

Apart from that: Anything that helps put you in the present helps. Cold water in your face is a good one. I use "measured breathing" Count 8 counts breathe in, 4 counts breathe out - slow and measured. Talk to yourself - tell your self you are safe, tell yourself whats going on around you. Better yet write out positive stuff like "I'm safe", I am (wherever you are), I am wearing, I see (name things you see), My name is______ Today is Wednesday Japril 17, in a pocket notebook and start reading them when you feel the start of an attack.

The big one is learning to reduce your stress so you can feel the build up to a panic attack. When you start doing that, you reduce the stress in the PTSD cup and you don't get to panic as often.
The second big one is stopping Rumination. There are a million threads on how to around here, but learning that piece is a big help too.