I don't know what the problem could be, but luckily you didn't take much. That's good, because that way your tolerance level won't be too high. I've been drinking for 15 years, but it's never hurt my stomach, although I have puked before because I drank too much. Did you try it on an empty stomach? By the way, red puts me to sleep, I prefer white or green for energy. Next time, buy several small varieties and try them out. I add min 50% lemon juice and drink it with chamomile tea. Thi