Water fast day 7...acid reflux???

Now and then (like this morining) i expirience acid in my stomach, sometimes i even burp some. I can't fanthom what this is since i'm only on water for a while now, and haven't had the problem prior to the cleansing. I also have a little strange breath, likes somthing is a bit off...any ideas what might be causing this? I'm drinking natural spring water wich has recieved the gold medal this year, beating the likes of Evian by an unbeliavable margin, so i can't believe it's the water. thanks Tweet