Sick one year old

My one and half year old has been so sick the last 3 days. She’s been pooping off white loose stools (before it was darker in color like normal), she throws up anything she eats or drink. She literally will not keep down food. I only got her to eat like 2 apple slices and 3 crackers all day yesterday and she still threw up 😣.

I took her to the doctor and she said it’s a viral infection and to just keep her hydrated and it’ll pass, but I’m so worried! I wanted to know if anyone else experienced this and what helped your kids (food, treatment, remedies etc)? She’s so tired all the time when she used to be so playful. 😥