Gave Amoxycilin For Cough, Body Ache Reduced, Unable To Expectorate Mucus, Chest Cracky. No Relief With Benadryl

Hi, I went to a doctor yesterday and he had given me amoxycilin as an antibiotic,my cough is already one week,and the hardest part is to expectorate mucus,my chest is so crackly,but by the time i will expectorate the only stuff that would come out is whitish saliva,nil mucus or any yellowish thick mucus,thus I still sound very crackly. i am working in a medical field,very expose to patients,thus i am afraid to go back to work. I tried benadryl,nothing happens,what would be the best way to do. I have taken three dose of antibiotic today. The cold is also still present,but my body ache is much better than previous days. thank you!