[Q] I tried trading someone for a game key, and they seemed clueless. What to do?

So I tried trading this guy: http://steamcommunity.com/id/8e8e7eewr344/ for his Borderlands: The Pre-Sequel game code, and now he's gone and said I'm a scammer (see http://www.steamtrades.com/trade/mRoA6/h-12-steam-game-keys-5-tf2-keys-trading-cards-w-borderlands-the-pre-sequel-steam-key-or-gift). All I did was ask him to use a middleman. I also put up 240 Steam Trading Cards in a trade--he just pressed "Accept", and then freaked out when I asked him what he was doing. Am I going to get in trouble with my reputation for this?