Quoting .:ANIMAL:.:" So, I've been cramping since yesterday. First I thought it was my period, then I thought it was gas, ... [snip!] ... hours so I'm slightly confused as to why both things looked like water. Has anyone ever had this happen? I'm a little stumped."
Sounds like it's bile. But bile is usually only what happens after your stomach has nothing left in it and you said that when you went poo it looked like water too so that is odd. But it does sound like bile. If you keep feeling sick I would go get checked out because if you are puking too much or pooping too much you can dehydrate very easily.