I shouldn't think an extra 3lb gain will make any difference to your looks whatsoever! You say your clothes still fit you fine - that means it hasn't made any difference to your size, doesn't it?

You say that you're binging at night. I imagine that means you're eating a lot of calories then. Maybe instead you could have small meals during the day - that way the urge to binge wouldn't be so great at night. It's your body's way of getting back on you when you've been starving yourself. I agree that it sucks.