This actually is one horror scenario of mine. Not the sweet Christmas Sam & Dean are having but the other kids. As I was a child and now as a parent I can't stand kids & teens comparing presents, trying to outdo the other with presens they have gotten for Christmas. Everytime I hear such dialogs I get very sad for another couple people have misuderstood the purpose of Christmas :(
But back to the story - I think you captured teen!Dean's inner workings really well here. How he struggles to make a perfect present out of some junk he found behind a dumpster :)