Weight loss in early pregnancy

Sarah
Over the thanksgiving holiday I noticed I've lost about 5-7 pounds according to our scale.  I haven't been really eating differently than normal (although I guess I am trying to drink less soda, but only drank 1-2 a day before).  I'm about 5 weeks and wonder if I just stopped retaining water (had been feeling bloated right before and when AF would've been due).  Anyone with similar experience?