It's definitely the beets. The same thing happens to me when I eat them. The first time it happened, I had that same moment of pure panic.
I thought for sure I was going to have to rush right over to the ER. Luckily I remembered eating the beets before I actually got in the car. I would have been mighty embarrassed if I had actually gone to the ER--not too mention how to explain the whole thing to my insurance company!
Since then, I've tried to stick with mostly golden or orange beets. They are much less traumatic.
