My 3 Year Old Has Had Beige Stool For The

My 3 year old has had beige stool for the last 3 days. Normal consistency. She was ill on Christmas Eve night, vomited two times, figured she had the stomach flu, as I had the same thing. Also had a little diarrhea. Since then she has been ok, but not wanting to eat, taking some fluids. Complains her tummy hurts. But then I noticed about 3 days ago her stool was beige. Tonight she just vomited again. Should I be concerned. I've read beige stool is not a good thing. What should I do?