Experiencing lower abdominal pains, also gassy. i had diarrhea once today and vomited a little in mouth. all this started last night. what could it be?

Virus: Sudden onset of diarrhea and abdominal discomfort is most often the result of a viral infection. Food intoxication can also be very acute and self limiting. If symptoms persist for more than 2 weeks, an evaluation for chronic diarrhea is warranted. If at any time symptoms lead to dehydration, if you develop bloody diarrhea, or if you simply cannot work, then you should see your doctor.