Suggest Treatment For Nausea, Hard Stomach And Diarrhea

I HAVE had nausea , diarehha for 3 days, went to dr and he gave me a pill for nausea . No more throwing up and there is nothing to throw up. my stomach is grossly extended and hard as a rock. any suggestions. I have drank ginger ale, Gatorade. just took one probiotic capsule today.