1578 Throe Down

So I was reading this story the other day and the main character was described as being in the throes of confusion. And I thought what the heck is a throe?
I mean, I know what a throw is as in throwing a ball. The ball was thrown. That pass was a great throw. But that's the throw that’s spelled with a W. What about the throe that's spelled with an E? It's usually written as a plural, as in the throes of confusion, the throes of agony, or death throes. Is there a singular version of that throe?
I wasn't that confused, so I only had one throe of confusion.
The dictionary definition of throe is a violent spasm or pang. A paroxysm. Well, there you go. You can have one throe after all.
And it's a pang.
So is there an exact equivalency? Can I feel pangs of regret that I only had one throe of agony over her departure? Or can I only feel one pang?
Speaking of meaningless words, I had a pang of regret the other day that I'd never researched the meaning of the phrase Uff da. What ever happened to Uff da? You used to see it on every third bumper sticker. Especially here in the Norwegian northwest. I always wondered what it meant.
Wikipedia, that ubiquitous source of all occasionally less than perfect information, says "Uff da" is a general purpose phrase meaning "I am overwhelmed."
Funny, I always saw it with an associated hand gesture, which made Uff da sound like a fairly devastating epithet. Not only that, it looked like a hurled epithet.
Such as, "Up Yours!"
Nice to know that apparently it can be used to just relate that you are overwhelmed.
Like, perhaps, being throe-n for a loop.
America, ya gotta love it.