You probably had a mild case of food poisoning with your system throwing out all the disagreeable stuff from your stomach or it could also be
gastroenteritis. Take an OTC lactobacillus preparation
and yoghurt with your meals. Drink plenty of fluids. Eat light, do not stay hungry but eat simple things like toast, porridge, cereals, crackers etc. Take ORS. Take over the counter antacid and antiemetic (this SOS for vomiting). Watch out for a day or two with this treatment.