Suggest Treatment For Fever

hello doctor, my son is 2 year old, yesterday he has got fever upto 101.7. At that time I gave him Calpol 2.5ml. Then in the morning his temperature come down upto 99.2. But after three hours again it come to 99.5 Symptoms are - Temperature is reducing & increasing Running Nose Naustril are choke up What should I do ? Please advise.