Mamabooshka Hope you get well soon!
Three times. First one was during high school, around 10th grade. I got hit by some stomach bug which makes you explode from both sides like the possessed girl from the Exorcist movie. I think there was at least 12 hours of mostly vomiting. That was followed by a fever which I was unconscious for the first additional 12 hours. After that, I couldn't really get up without my vision going black. Think I was out of commission for only 3 or 4 days though, I remember out of all my teachers, my science teacher called my house concerned.
2nd was very mysterious. I went to sleep feeling off, and woke up to vomit. Had a pretty severe chest and head pain, and had a cough for awhile afterward. Think it was some pneumonia or something.
Last but not least... This wasn't bad, but it was also during exams. I had a cough so severe that they sent me home immediately. Haha!
I guess the whooping cough during elementary school was also pretty bonkers.