Suggest Medication For Bronchitis,chest Heavyness

Hi I ve been sick for 8 days. On weds went to the doc.my symptoms were chest heaviness dry cough scratchy throat hoarseness n acheness. She said it sounds viral but could b the start of something worse like bronchitis. She gave Me an antibiotic cephalexin to start on Thursday if I wasn t feeling better. I started the antibiotic on thursday. Friday I still had the same symptoms but added some new symptoms stuffy nose, sneezing, sinus pressure acheness. Today the scratchy throat hoarseness all went away till I lay down and the chest heaviness isn t as bad but gets worse when I lay down. I have no sneezing anymore. But new things I m really weak much worse then before n have no energy. I feel really tired. My pulse is 114. Any ideas what s going on.