Hi, I have someone i know with some weird kind of...

Hi, I have someone i know with some weird kind of problem. Can't really tell what it is, well she has stomach problem, she has that since she was a small child and it slowly faded but the problem is still there and at times after eating, sometimes after rly have sugary stuff or something normal food, she feel like somethings wrong with the stomach and she feels often cold too at night and during the day sometimes , it might be cuz the weather is cold but even after being covered she feels cold and feels like throwing up and has headache and almost feels like fainting and also there is shivering. But after getting warm the shivering stops but the headache is still there and stomachache disappears after passing out gas or burping after drinking a fizzy drink or lemon water with something her mom gives her. She is 15 years old and has no previous medical issues. Access to any doctor is quite restricted so she hasn't seen any doctor before.