Have you read these?

Do Your Duty, Little Sparrow (http://rainylemons.livejournal.com/32405.html)
Dean goes missing searching for someone who might be able to heal Sam’s permanently ruined leg. In the course of searching for him, Sam and Castiel fall into a trap and Sam suffers an asthma attack.

The Other Guardian (http://ladybastet92.livejournal.com/79430.html)
When Sam goes missing, Dean isn't the only one who worries.

Unbearably Cold (http://ohsam.livejournal.com/539466.html?thread=3341386#t3341386)
Sam is hit by a curse that leaves him unbearably cold. Cue Cas holding/cuddling/wrapping him in his trench-coat to help get him warm while Dean tries to find a way to break the curse.

This one is more emotional hurt rather than physical.
What We Can Learn From The Amulet (http://www.fanfiction.net/s/5870733/1/What-we-can-learn-from-the-amulet)
Sam's reaction to Dean throwing away his gift seems extreme to Dean, but why is it justified?
Warnings:- Will contain graphic references to non-con and child abuse.
Also, this is a WIP.

EDIT:- Okay, just saw your username and realised that you actually wrote The Other Guardian, so I think it's safe to say you have definitely read that one, lol. My bad. Awesome fic btw, I love it. :)