Most probably sick from eating too much, stop eating for a while and let your stomach settle. Have a stock of food and water in your bag and eat regularly to avoid the "Thirsty" and "Hungry" message so that the healing process starts. It's very complicated and not very realistic in my opinion, the character eats a lot of food. In a survival situation you can stay alive a long time (several weeks) without food and simply drinking water. I know, it's a game, and if it was too realistic we'd probably get bored very quickly. Just sucks to die from "hunger" after a few hours. Doesn't make much sens.
