[hedonist]

I wouldn't say it felt like dying, but yes, I once had a very strong panic attack with symptoms like this.

It was actually helpful (in retrospect) to consider the experience in terms of a temporary glandular over-reaction of some sort. As in, not "aww look how broken and pathetic I am to be all curled up in a ball like this", but rather, "look at what a complex feat of engineering I am, and look how helpful it is of my body to warn me and signal me when I'm exposing it to stresses it doesn't like very much."

So you might want to look up the terms "cortisol surge" and "adrenal fatigue". And also look into that magical chemical known as serotonin, and how it works as a cross-regulator among various cognitive and strictly physical subsystems in your body. Mind you, I've had no formal medical training, I'm just saying a bit of self-study and serious research might be helpful here.

As to how to prevent them: that's a touch one, because everyone has different trigger thresholds, and (despite what big pharma would dearly like for you to believe) there are no magic bullets.

But personally I've found a sustained, low-key meditation practice to have surprisingly positive long-term benefits. When you strip away the paranormal- and pseudoscientific baggage around it (which are really just that), what it comes down to is (1) basic common sense awareness of how mental and emotional stress works in the body, and in particular, how it correlates with physical stress; (2) how easily we fall into "monkey-mind" patterns of reacting to stressful situations, rather than simply detaching from and (mentally) walking away from them, as it were; and (3) how the same natural tendency of our minds/bodies to learn counterproductive reactive behaviors, can, over time, be used to "unlearn" them, and with surprising efficacy.

But in general -- increased awareness of how our minds and bodies aren't really separate things, but different manifestations / aspects of the same, unified (and beautiful) thing; couple with a realization of how much potential we really have (despite all of our past mistakes, and all the crummy things other people do to us, or say about us), can really help quite a lot.