BECAREFUL OF LIPTON ICETEA!!!

I am highly allergic to caffeine Bought Lipton icea tea, when i read ingredients there was no mention of caffeine so i drank it and after 30 minutes started feeling sick, i went to the hospital, the following day i started vomiting blood. I contacted Pioneer Foods and they sent someone to come and collect the remaining icetea. After some days i called them to find out How much caffeine content was in their iceatea since they said they are going to check? What other ingrediant do they put which is not listed on the list? The lady who said she is the one responsible for complaints said, "You shouldn't have drank it because it's tea and we can't know for sure how much caffeine was in there because the sample we collected from you was too little", when i told her that doesn't make sense she hung up. I wonder what other ingredients are put in Lipton icetea to get you hooked up on their product which are not listed on the ingredients list?