Can I Give Calpol With Ondem To A Toddler After They Vomited Multiple Times, Has A Fever, And Isn T Eating?

Hi. I have a 17 months old baby boy. He vomitted a lot yesterday around 7 pm, once. Later around 9 pm, he had vomiting tendencies again. He didnt eat anything nor had any milk. We gave rantac syrup and made him sleep. Now again, around 2am midnight, he got up and vomitted again. Gave him ondem 2.5 ml. But also he is having fever.. but still not eating anything. Can i give calpol along with ondem? No signs of loose motion yet. Also suggest how frequent can i give these medicines?