waterweight?

how much waterweight is it normal to be holding onto?
i recently started at a gym after having my baby girl  
i been working out for around a week and yesterday morning i checked my weight and i thought my weights were broken!!
i had dropped 14kilos/30 pounds!! does anyone know approx how much of that could have been water/fat? i know there is no way to know fr sure without one of those fancy scales that some gyms have. just interested in seeing if anyone has some experience. thank you

Did you drop 30 from what you weighed before or after giving birth?

my weight before and after wasnt really too different. but technically after