Hello! I have been through your question. Related your symptoms I think this is an intestinal infection but the cause could be viral(norovirus, rotavirus) or bacterial (Salmonella, shigella, E.coli ect) Intestinal infections can be serious depending on the microbes which have caused the infection.You should know that symptoms of an intestinal infection could be some like watery diarrhea and some time bloody, abdominal pain, fever, headache (sign of dehydration), nausea and if symptoms persist for several days as you have it is important to do a physical examination by an Infectious diseases specialist, do a full blood count, azotemia /creatinemia( to see renal function), electrolytes, and sample stool and stool culture to define better the diagnosis( if is viral or bacterial) and to start the treatment ( with antibiotic if the cause is bacterial like salmonella, E.coli, shigella and ect). Furthermore during this time I suggest to drink a lot of water and tea and take probiotics. I hope my answer help you. I wish you a quick recovery.