you can be hypersensitive to mutton proteins due to presence of antibody against its protein or carbohydrates which has formed due to previous sensitisation and now causing allergic symptom .allergy against egg protein or meat protein is quite common, to confirm it you must go for complete pannel allergen test , it will also rule out other allergic substances.it happens due to Immunoglobolin E and histamine and produces symptoms almost suddenly after intake of allergic foodsand it is needed to be treated early as it can cause severe respiratory and cardiovuscular sympoms if left untreated. it can be due to irritable bowel syndrome and to prevent it you have to avoid meat consumption and other greasy spicy food also. it can be intolerance due to inadequate amount of enzymes required to digest the meat content which causes symptoms after few hour of consumption.it is different from allergy and need a different treatment including low intake , intake of enzyme etc. so you should meet a physician to diagnose the condition and then go for its adequate treatment. thanks and with regard.