Hi, my 2 1/2 year old son started a fever Thursday that lasted one day along with vomitting. On Friday he had diarrhea only, all he ate was chicken/corn tortilla, Gatorade, and milk, but at night he pooped what looked like small white cheese or egg white. It smelled like milk gone bad. Saturday he continued with yellowish diarrhea, but on Sunday morning he pooped a dime sized egg white substance again. What could it be and what should I do?