6 month old has Viral Gastroentiritis

Looking for some thoughts/advice as my doctor diagnosed viral gastroenteritis in my 6 month old over the phone but theres no sign of any improvement. It has been about a week and a half, it started with her refusing most foods (we have only recently started weaning but it had got off to a good start and now we are falling behind). We then noticed she had brought up some of the food in her cot during the night and was being sick several times in the day (not projectile). The sick has mostly stopped but we have had leaky nappies for a week and a half, her poo is yellow and very watery. On top of this, whilst she is happy most of the day she is refusing to nap in her cot and will only nap on one of us, and she has had a few outbursts of really distressed crying without an obvious reason. Any ideas how long I should expect this to last and whether this could be something else? Thanks