Only that you may be restricting calories too much. For some of us (myself included), if calories are too low, it slows down the metabolism. The reasoning is that your body becomes aware that all of a sudden, it isn't getting as much "nourishment" (calories) as before and slows down in order to conserve (evolutionarily speaking, in case of famine). You may see better results if you bump up to, say, 1400 calories a day. Sounds paradoxical, but it often does the trick. How many calories do you burn a day total, between lifestyle and exercise?
Also, time of the month can affect weight (you can gain 3-5 pounds easily the week of and week before), maybe that's a factor?
"If you drop an egg, you don't say, 'Oh, shoot' and drop the other 11, do you?"
-Source unknown, but obviously brilliant
Reached goal 4/16/2010...but kind of afraid to look these days