Lactaid and bed rest

My story is very similar to the others here. I had taken Lactaid a few times without any problems. I did take two a little over a week ago with dinner and about an hour later I was violently vomiting. I had never been that sick before. It continued for a couple of hours, and I finally went to sleep with terrible pains all over. It took a few days to feel like myself again. I thought originally it must have been food poisoning from the restaurant. Then the other day I took two more with breakfast and the same thing only worse happened. I vomited so hard I thought my back would break. Bed rest for the rest of the day with chills and pain. Now its my third day out and I'm still feeling nauseated and weak. Pepto Bismol is not helping either. I just want to feel better again. I got rid of all the Lactaid in the house as two of my children take it also, but there is no way I'm taking a chance with them. I felt like I was going to die from poisoning or something, I can't imagine a child going through this.