Basically what this means is that your body does not want water. Try hot water and drink it like tea, just a few sips. Although this is one of the symptoms of fasting, I would suggest listen to your body. If you feel that continuing the fast will harm you and there is no way you can continue, you should break the fast. But if water is staying down, most juices will not either.
Please put warm coconut oil or castor oil on your stomach and gently massage it.
I hope that this stage passes soon. My heart goes out to you. You have done a great job.