Before starting the fast I read that you should drink as much water as you can each morning when you wake up. Even in excess of a couple of litres. I have been doing this and usually drink 2.25 litres and sometimes 3 litres depending on what I feel like. I often have another 750 mls during the day sometime if I've been particularly active and feel parched afterwards. The idea is supposed to be to really hydrate your system, the water being absorbed through the intesinal walls into the blood and from there to the organs and even down the very cells themselves, washing everything out. The symptoms you describe sound more like the symptoms I have had on my dry fasts and fasts with very little water, though of course everyone will be different my experience with Water Fasting has been completely comfortable with no aches or other concerns so far.