So a couple of years ago I read a story at ff.net which I forgot to bookmark and can't find anymore.

It was a story that took place preseries and Sam could not have been over sixteen. Although it wasn't specifically mentioned, you could guess due to his behaviour that he had developed an extreme case of OCD. I think - I'm not sure though - that Sam acted the way he did to gain some control over his life, as he was so unhappy travelling with John and hunting monsters etc.That being said, it was a really angsty story.

I only remember that one specific scene, where John(?) spilled something on the carpet of a motel. Sam hardly contained himself from cleaning it right away, as he didn't want his family to know of his coping mechanisms. However, in the middle of the night he stood up, took the bleach, and desperately tried to get the stain off. Dean woke up, initially to drink water or something, and saw Sam on his knees, scrubbing the floor. I don't remember Dean commenting on it though.

I don't know whether it was a one-shot, but if it was multi-chaptered, it couldn't have been too long. Also, I'm pretty sure that there were no pairing or romance in general.

Thank you in advance:)