Hi. Thanks for your query. Noted the history and understood your concerns. Stomach cramps with vomiting van be due to food poisoning as you have correctly guessed. There may not be fever in gram-negative septicemia and yet have headache due to septicemia. Loose stools may ensue later on hence watch out for symptoms. I would advise you the following in such a situation: Get a stool and blood test done to know the exact clinical correlation with the symptoms and thus get started with a symptomatic treatment with a PPI like Omeprazole, Domperidone for nausea and vomiting. Paracetamol for headache. Antispasmodic for cramps if required. Probiotics. Antibiotic and metronidazole if the clinical or lab tests indicate so. Boiled cooled water and homemade fresh foods only.