not enough fluid?

I went for a check up yesterday (32weeks) and they said baby is growing great-3weeks ahead- but said my fluid in the sac was boarder line low and that I need to keep drinking water. I am drinking so much water it's crazy I feel like I'm a walking water balloon. I'm nervous that when I go back in two weeks what they are going to do/say!! Anyone have experience with this and what happens? Sorry FTM here.