Hello! I have been through your question. According your symptoms I think this is gastroenteritis. Usually, the cause is typically a viral (norovirus, rotavirus) or bacterial infection (E. coli or salmonella).The way that gastroenteritis can be spread is contact with someone who has the virus, contaminated food or water, unwashed hands after going to the bathroom. Usually to define the real cause of gastroenteritis you should do a stool sample .What I suggest is that you should talk with an Infectious Diseases Specialist, do full blood count, azotemia and creatinemia (to see renal function),stool sample (bacteria and parasites) and rapid stool test (for virus)and to decide to take or not antibiotic (if caused by bacteria,usually ciprofloxacin or bactrim). During this time yous should follow some advice like drink a lot of water and tea with tresol, take probiotics , and don t drink milk or carbonated drink don t eat food prepared outside or fatty, eat only toasted bread, yogurt,cheese, boiled egg, banana. I hope my answer help you. I wish you a quick recovery.