I'm a perfectly healthy 15 year old girl, but within the past year I've had this weird illness that only lasts about a day then it goes away with no signs of it ever happening. It's happened 3 times so far, getting worse every time. The first time, I just became very nauseous and had horrible stomach pain. The back of my neck hurt and I couldn't get comfortable laying down. I ended up throwing up several times that day but I was perfectly fine the next day. The next time after that, I didn't throw up but the nausea was worse and I was just exhausted the entire day. 2 days ago, it happened again but was worse yet. I woke up in the morning feeling fine but shortly after, I felt nauseous and knew it was the same feeling again. I took a nap and when I woke up, I had a headache and was hungry. I went to get food but I was shaking badly and I just knew if I didn't sit down, I was going to throw up or pass out. I felt very unstable and I sat down, but I still felt awful. I stood up to go lay down and as I was walking, my vision started to go away. It looked like I was looking through TV static and I felt like I was really going to pass out again. I literally could not see anything past the "static". I got extreme cold chills and broke into a horrible cold sweat and I was still shaking. I ended up laying in my parents' bed because I knew I couldn't make it up the stairs. As soon as I laid down, the vision problems left and the chills started to subside. My dad thought my blood sugar had gotten low (I'm not diabetic, I don't have chronic low blood sugar) so he had me eat a candy bar and then dinner. That didn't help. I also had a drink which helped some, but not a lot. I stayed in bed for several hours and eventually felt good enough to go back to my own bed. The next day, I felt a little bit off, just kind of sluggish and tired, but otherwise fine. I would see a doctor about it, but when I'm sick, I truly feel like I can't go anywhere without passing out and I don't know if it's worth it to go when I'm not showing symptoms anymore. Does anyone know what this could be? Feel free to ask questions if you'd need more background information or clarification. It just feels horrible and I'd like to know what it could be. Thank you!!