Disclaimer: I own nothing to do with Supernatural. I wish though... my birthday was yesterday, so maybe they're still in the mail?
No one could ever accuse Dean Winchester of being afraid of pain. He had never been allowed to be. From the time he was four years old, his world had revolved around pain. Pain and fear. And besides, how could you cry over a scraped knee when you got attacked by werewolves, beat badly in fights with unearthly creatures, and put through punishing training exercises by your own father? But what most people, even Sam and probably John as well, don't know is that some part of him actually accepts it. No, not even accepts it… part of him actually enjoys it.
Not that he was some kind of masochist. He didn't keep chains in his bedroom –okay, well, maybe he did, but not for sexual reasons- and he didn't get off on some butch chick with a whip making him call her "Mistress". But the pain he encounters in the line of duty was different. More noble, perhaps.
Sometimes after a fight, every part of him hurt. Dull aches in his muscles from overexertion, deeper aches from bruises where fists, feet, or weapons had struck him, sharper pain from the occasional knife or bullet wound. He whined when Sam treated the wounds, but that was for Sam's benefit. If he sat silently while his brother patched together torn skin, broken bones, or whatever, it would probably scare the crap out of the younger Winchester. Because no normal human was this accepting of pain.
And it wasn't always the major stuff. The pain in his back when he drove for 20 straight hours on the way to another job, because even though Sam offered to drive, he was asleep when Dean started to get tired. Actually sleeping peacefully for once, not twitching or whimpering from a nightmare, so there was no way Dean was going to wake him up just so he could rest a little. His kid brother so rarely got good sleep anymore and he could handle it just a little longer.
Sometimes the credit cards got cancelled and he couldn't find a pool hall or a poker game immediately. Sometimes they would miss a meal or two. He could usually slip a candy bar or a bag of chips into his pocket, but the gas stations kept the real food, sandwiches and pizza and stuff on the counter so there was no hope there. He used to just steal food for Sam, until his brother realized that and refused to eat anything until Dean had eaten as well. He tried to explain that he would be okay for a while, but Sam got made, said he wasn't weak and would be okay too. Neither of them had eaten then, and Dean learned it was just easier to get enough for two.
Sometimes the cases the police got in their way, suspected them of doing whatever they were there to kill had done, and they weren't always quick enough to get away. Sometimes they wound up handcuffed and in holding cells. Dean didn't really mind other than it cost them time (and maybe someone else their life, if whatever they were hunting was particularly vicious) as long as it was just him. As long as he was able to keep the cops' attention and let Sammy get away. The whole skin-walker case had nearly killed him, if for no other reason than because he had to run and leave Sam to deal with the cops alone. The rest of that mess was bad enough, but having to abandon him like that was rough.
Sometimes they were too late. Sometimes people died because they stopped for the night to get some sleep before finding their prey, or because they stopped to have a burger or a drink. That knowledge ate at him, sometimes haunted his sleep. But he never mentioned it, brushed off the rare occasion where Sam caught him in a nightmare by saying it was a falling dream, or a plane crash. He wasn't entirely sure Sam believed him, but it shut him up.
But there was one kind of pain that Dean Winchester couldn't endure. The fire tearing through his gut, radiating from the blade of the knife the vampire had left embedded there before Sam had beheaded him with one swipe of the machete, was bad but bearable. He had been through worse. And yeah, he might need a hospital but it wouldn't be fatal. He would live. There had been worse pain in his life.
But Sam was kneeling beside him, frantically trying to stop the bleeding, babbling about how he was going to be okay, the bloodsucker was gone, they were going to get him to a hospital, it was all going to be okay. Then, having done all he could, he stared into Dean's eyes for a moment, tears glistening unshed in his eyes. "You jumped in front of me, man!"
Dean tried to shrug. "You were fighting the other guy. This one would have killed you."
"So you thought letting it kill you was the better plan?"
" 'm not dead…"
One stray tear escaped Sam's eyes, but Dean wasn't sure if it was from fear, hurt, or anger. Or all of the above… "Not for lack of trying!" Sam took half a beat to compose himself, to put his game face back on. There was work to do, he had to get Dean to a hospital. "I'm gonna pick you up. Hold still."
"Sammy, I can-"
"Shut up." Sam scooped him up, which sent another flare of pain through him, but it was acceptable because walking would be rather difficult. Sam never staggered or stumbled and Dean wondered briefly if this was one of those adrenaline things he had read about. But as he was carried to the car, he noticed Sam's shoulders and chest trembling. Not with exhaustion or exertion or physical pain.
"Sam?" Dean asked tentatively. "You okay?"
"Sure. Fine." His voice was terse, tight, with only a minimally detectable crack in it.
"Sam…" Dean wasn't sure how to proceed. They reached the car and Sam very gently placed him in the passenger seat. "Talk to me. What's wrong?"
Sam sat in the driver's side, face twisted in pain for a moment, debating whether to say it or not. "You could have just yelled, or thrown something at me! I could have lost you tonight! You pretty much sacrificed yourself for me!" Dean was about to ask what the problem with that was, but thought better of it. Finally, the tears broke free. Looking at Dean, raw agony in his eyes. "I could have had to watch you die. Do you have any idea what that would have done to me?" He looked away for a moment, gathering his courage, then looked Dean right in the eye. "Please, Dean… Don't ever do that to me again."
Everyone has their breaking point. He could take anything else, but the one thing Dean could never endure was his brother in pain. Even if it meant lying to him. "Okay, Sammy."