Hi I just came back from Mexico and I tried really hard not to drink the water but I did have mixed drinks with ice, so that may have to do with this. My stomach has been bothering me for the past three days. It's gotten a little better but it doesn't go away. I drank a lot of alcohol the night before it started hurting so I thought maybe it was that, but I don't think it would have lasted for three days. Could it be the food? I'm nervous it is a parasite. What do you think?