For starters I should mention that this was for my booster shot. I had received my initial vaccine which was Johnson and Johnson on October 22, 2021 and was also 22 at the time. I had some severe symptoms after my initial vaccine such as violently shivering, cold sweats, migraines, and nausea. I assumed it was normal until I received my booster. I received the Pfizer vaccine as my booster on February 2, 2022. I had explained to the nurse my worries about symptoms and side effects considering the severity of my symptoms for the J&J. She assured me that it is important that I stay hydrated and rest which is exactly what I did. She also provided a packet of information. I received my Pfizer booster vaccine at 12:00 pm on February 2nd. The first time I started to feel symptoms was about five hours later when I was resting in bed. I began to feel warm as if I was getting a cold. This lasted until about 10:00 pm when other symptoms began to occur. Again, I had been keeping myself hydrated by drinking a lot of water since I got my shot earlier that day. At around 10:00 pm I started noticing similar symptoms to the ones I had after the J&J. This includes violently shivering, sweating, nausea and headaches. I also began to feel body aches apart from my left arm (where I got the shot). At around 11:00 pm I began to get frustrated as I was extremely tired so I decided to take some Advil. I took 2 200 milligram tablets. I have been taking Advil for many years and do not take it often. I have also never experienced any negative side effects from taking it. I was able to fall asleep fairly quickly as it helped my body aches and head rest for a bit. I woke up for the first time around 12:30 am. I was laying in a pool of sweat and my body was violently shaking (shivering) as I felt cold but my body was burning to the touch. It was at this time I began to hallucinate as well. I have never hallucinated before and it felt as if my physical body was not real or that I was in some kind of alternate reality or "dream world". It sounds crazy but it is hard to explain and was utterly horrifying to be completely honest. My whole body was in excruciating pain at this point and it physically hurt to move at all. The next few hours up until 6 am I am not sure if I ever fell asleep or if I was hallucinating it all. I "woke up" again around 2:00 am. I went to the bathroom and had thrown up everything I had ate the day before along with a lot of the water I had consumed. I had stayed in the bathroom for around 2 hours I believe until I was dry heaving and throwing up bile. I then returned to my bed where I assume I fell asleep again. Over the next two hours (4:00 am - 6:00 am) I woke up every 15 minutes. I again do not know if I really fell asleep and woke up or if I was still hallucinating. I did not fall asleep again after I "woke up" at 6:00 am and did not sleep/nap at all that day (February 3, 2022). I had still felt warm to the touch and had both a bad headache and stomach ache in the morning but felt much better as the day went on yet the painful stomach aches lasted a total of three days. During those three days I was not able to eat anything without fear of throwing it up. On February 3rd I had made some toast and took one bit and gagged so horribly that I almost threw up and I was not able to eat food again until February 6th and to this day (February 8th) have not had much of an appetite at all. Overall, both experiences I had were scary but my booster (Pfizer on February 2nd) was absolutely horrifying.