It does get kind of gray. How long had it been in there? I wouldn't have tossed it if it was still within the 10 days. You're storing it right. The only thing different is, I store mine, after the initial refrigerated rise, with the lid on tight. I keep my fridge pretty odor free, but I don't like the idea of food odors getting in my bread.

eta: Oh, duh. a week. It was still good. It's going to smell heavenly yeasty, which may translate to stale beer.

Karen