I had a similar experience here in the USA: I dropped a section of plywood on my big toe. It hurt so much, I was sure I'd broken the toe, so I went to the emergency.
The emergency room doctor determined it wasn't broken, and then dug a little hole through the nail. Blood spurted out, and the pain was reduced by 90% immediately. It seems blood builds up in what is called a hematoma, and the pressure causes pain.
The same thing happens in the skull sometimes. That's one thing I never want to experience.
Oh, and the bill was a cool grand, that's right, $1,000 US dollars.