My 2yr old son was congested, sneezing, coughing , had a temp of 102.4 and was having green/yellow drainage from nose. I took him to pediatrician, He was diagnosed with a sinus infection on Saturday and MD ordered Omnicef 3cc everyday for 10 days. Today is the 3rd day of the antibiotic and he currently has a temp 0f 101.9 under his arm. Is this normal after 3 days of antibiotic.