I think I'm doing this wrong...could use some help.

So I've been playing since the game came online but I don't have a ton of time to devote to gameplay. As such, I've only just gotten my first lvl60 char...my barb Ajax. I got to Inferno the other day and realized I needed to upgrade my gear. I had exclusively played as a 2-hander, but I thought, if I dual-wield, I might be better off since I would have affixes from both weapons.

So I spent some time farming in Hell and spent a few 100k gold on some new one handed weapons. Imagine my surprise when I went from

My Two-Handed Build's Damage of 28539.57

to My Dual Wield Build's Damage of 18752.94

What am I doing wrong? Any advice (on anything you might see wrong with what I'm going) would be appreciated!