Hi My 2 Year Old Son Is Having Fever From

Hi my 2 year old son is having fever from past 4 days.he is having runny nose thick mucous coming out of the nose.n he is coughing a lot.unable to sleep in night.doc has suggested ambrodil s 5ml thrice a day n zyrtec 5ml twice a day. N crocin 7ml for fever.medicines are given from past 3 days.he is not improvng n coughs are getting more.fever is also not going.what should i do.plz help