Amniotic fluid

So my amniotic fluid is low because of not getting enough water. The thing is I do drink water everyday because I know if this risk but I can’t keep the water down I tried taking small sips or putting lemon in my water but I start throwing up I told my doctor this but she told me as long as you drink whatever amount of water you should be fine but how is that going to help if I can’t keep it down. Has anyone had this problem is there something I can do my nausea medicine doesn’t help. I’m really worried for my baby.