Thanks for your query.
Your son is having features of acute gastroenteritis
which is mostly viral in nature and settles in few days.
Most important is to maintain proper hydration.
for fever if it is more than 100F.
Give oral rehydration solution sip by sip after each loose stool
,give coconut water,lemonade.curd.rice porridge.banana.
In case of persistent vomiting/fever/lethargy/decreased urine output get him examined by pediatrician
for further management.
Wishing your child early recovery.