Thanks for writing to Health Care Magic.
Your baby is having diarrhea
which is viral in nature and settles in few days.
With any infective process appetite is decreased.
Do not worry about it.
Give oral rehydration solution after each loose stool
,give coconut water,lemonade,buttermilk,curd.
like lactobaccilus for 2 to 3 days.
Wishing your baby good health.