What Causes Persistent High Temperature And Running Nose In A Toddler?

Hi my son is 3yrs n 2 months. He has been suffering from cough/cold since early Jan (on/off). We recently relocated and the climate is very cold. He has once again cough n runny nose with heavy chest congestion. Been running high temp of 101-102 deg C at nights/early mornings. Have been giving him Levolin 3.5ml & Calpol 5ml Could you pl adv if same to b cont. As no +ve results for d past 2 weeks (fever for 4days nw) ... He really finds it so diff.. Pls adv... Thanks!