What's the most painful injury you've sustained ?

Easy. Sprained knee. Unbelievably painful. I was up two days straight partying on pot, cocaine and alcohol. After 23 double shots of tequila I was dancing like a lunatic to the song Wish by Nine Inch Nails and snapped the cap off my knee to the side. I fell down, poured myself 2 more double shots, grabbed my pant leg and pulled my leg straight. It snapped back into place. I saw this flash of white light from the agony, then a shrinking black tunnel formed around my vision. I managed not to black out and it swelled up like a balloon almost immediately.