When I was about 17 or 18 I was working on an old truck with my dad, and we decided to jack it up and beef up its offroad capabilities. That truck was an injury mill. In one particular instance where I feel real stoooooooooopid, I was one-handing a 3lb mini sledge while trying to persuade something or another to move when the sledge slipped when it struck the punch and inadvertently crushed my right thumb and index finger. The worst part was that my index finger was sideways, so the nail tore my finger all to hell. Both instantly started swelling and I had blood blisters on the finger itself, as well as under the nail. I had hit the thumb so hard that it tore open, almost as if I had smashed a sausage or something.
When I hit it, there was absolute silence - you could have heard a pin drop in the garage, then I raised up, hit my head under the truck while extracting myself, and started dancing around in the garage. My old man (RIP) saw exactly what happened, and just as straight faced as you could imagine, deadpanned "Why'd you do that, Steve-O?" to which I said "Because it feels so damned awesome." before walking out the door and throwing up.
I could still move it, but the nail was throbbing, so I took a tiny little drill bit and drilled a pair of holes in each nail, then pierced the blisters with a needle. There was so much blood under the nail that it shot out a couple of inches - almost thought I hit an artery or vein or something. That was the worst part. It hurt worse than when I hit it, but afterward, I finally had a bit of relief - until the next day when my fingers were sore as hell for the next two weeks.