What could this be?

Jennifer • Jennifer King

So I've lost 18 pounds so far and I'm 16 weeks 3 days. I seen the OB Monday, weighing 246, I haven't changed anything I eat and I still exercise for 30 minutes a few times a week. I weigh this morning before I eat or drink anything and scale says 252!!!! 6 pounds in 3 days?! I do drink a lot of water over 10 glasses daily, faithfully. What could this be?