Dear student.
This might be due to food poisoning as a result of spoilage of food.
Food poisoning is illness that arises from the food that we consume. Illness may be due to pathogenic microbes present in food (such as bacteria, fungus, virus), toxic chemicals in the food (such as pesticides, food additives etc.), natural toxic substances (such as poisonous mushroom etc.). Food poisoning is due to improper storage of foods, improper handling, washing, cooking, food adulteration etc.
Regards.