I understand your panic attacks. I've had them. Sometimes they are so intense I wanted to cut open my veins to let the panic out, but fortunately there is something that stops me. I understand that at the time nothing makes sense. There is nothing that triggers my panic attacks. The feelings are completely scrambled.
I use Xanax regularly and can take more if I need.
What I did learn while in a partial hospitalization program was DBT (Dialectical Behavioral Therapy). DBT helps you develop plans you can use when these attacks hit, I have several that I use based on what's happening. I keep them with me at all times.