Incidentally, at the time, I was terrified and when I came round I was out of breath and hysterical. Nowadays, though, when it happens, it is possible to reassure yourself by keeping calm and saying (in your mind) "It'll stop in a few seconds". Admittedly, the seconds feel a long time. Also, another thing i do is, if I feel an episode coming on, I begin to wiggle my toes, with all of my strength and effort, and inevitably it "wakes" my body and I come round quicker.
P.S. I'm not mental