Bizarre!! Reaction to a sting or bite today

[Ginevra]

I know, two posts in a couple of hours after I’ve been limiting myself to a max of 45 min per day on here. But this is where my smart friends are, so...maybe someone knows about this. 
 

So, firstly, I am amazingly susceptible to mosquitoes. Like, I’m apparently a walking buffet to them. So I douse myself in bug spray 99% of the time, even just going to my garden or the chicken house. But, I didn’t do that today before I walked out to my mailbox. 
 

As I got back to my door, I noticed what I expected was a mosquito bite on my wrist, which was starting to itch and sting. I came inside and put benedryl on it. Within a few minutes, it was burning like fire and itching like mad. My whole wrist started to welt up about the size of a quarter, but it had a jagged edge running over to my visible veins. Then, moving up from my wrist to my armpit, I got red, burning, itching welts in random stripes and splotches. It hurt and even hurt deep in my bicep, like a bruised muscle. 
 

The whole episode abated within an hour. What in the actual world was this??

I have a short video, which I’ll try to put up but it might be too big.

[Guest]

21 minutes ago, Æthelthryth the Texan said:

Also, I mean asp the insect, not the snake, obviously. But it sounds/looks like an asp reaction. I am just concerned if it's on your affected arm re:lymph nodes is why I asked, to clarify. Sorry, trying to Hive and Puppy at the same time. 

If we have asps (the insect), I have never heard it mentioned. Yes, it is on my affected side; that is a good point. That side has never been completely right since surgery. I had Axillary Web Syndrome.

[AmandaVT]

That looks similar to what happened to me when I got bitten/stung/stuck by a hickory tussock caterpillar. I hate those guys! 

https://www.cbsnews.com/news/venomous-canadian-caterpillar-spotted-in-pennsylvania/#:~:text=If you see the white,also also irritate human skin.&text=More importantly%2C it has hairs,back contains rash-giving venom.