If your body deals with TOM like mine does, you will probably have a good weigh-in next week. I gain water weight 3-4 days before I get my period, then within 2 or 3 days of starting, I lose all the water weight. When I was losing, I would lose the water and then see a new low weight on the scale, a half a pound or a whole pound below my previous low.
However, I suspect that, like everything else, everyone's body is different. Pay attention to your weigh-ins for a couple months and you will notice a pattern. Yes, we all over-think a little about the scale when we're losing, but the advice is always the same. Take a deep breath, relax, and remember: the weight will come off, just not all in one day!