All of you have it wrong. It's your amygdala. It's in over drive. The catalyst for your anxiety/panic attacks is not important. What is important is diverting yourself with every thing possible, meditation, and anything you can possibly do to form positive habits. You've gotten yourself into this from having bad habits (Dwelling on anxiety etc) you need to switch your high anxiety switch to off, and get it back down to it's appropriate level. I was strangled a year ago and since then, I had the worst anxiety I had ever experienced. I'm still doing this linden program but I downloaded it. It only works when you have all of the program (Torrent sites cut out some of it when I downloaded it =( ) But this is a scientific reason as to why you're suffering like this.
We are suppose to have anxiety but not high levels unless you're being chased by a lion. This is like being terrified of a rabbit behind bushes. It's like being afraid of an itch. These are sensations you're experiencing, including physical and physical sensations come before anxiety. Mine started after drinking too much caffeine, then the panic, I felt like I wanted to die, I wanted to kill myself then so the pattern starts. Physical, then mental. It is scientifically proven.