Yes, a couple of times I had what's called a "vagal spasm", and it did feel quite scary at the time, though didn't last very long. Thank goodness I was on my own so there was no-one to fret about it or cause any dramas.
It is the weirdest feeling isn't it?
I thought I might have a near death experience! But no.
I was so upset about the thought of dying on the toilet that I forced myself with superhuman strength to wipe, wash, and get cleaned up. Then I had a shot of brandy.
Within a few minutes I was OK enough to walk a quarter mile to feed a neighbour's cat (I had agreed to do that when they were abroad.)
I find the odd thing with a vagal spasm is it feels so bad, yet may never come back, or if it does, it could be a long time until it does.
I had no negative effects after it.
But if someone gets them every day, I would think it's time to get it checked with a doctor.