I started getting ear pain after a cold. pcp rxd a zpack for strep and ear pain. a week later finished medication and pcp rxd amoxicillin for ear infection. she also mentioned i have fluid in my ear. what does that mean ? did the z-pack not work ?

Retained middle ear fluid is part of what allows an ear infection to develop. It originates as mucus from the walls of the middle ear & during healthy periods will drain through the eustachian tube to the throat. Colds can plug the tube & mucus builds. Germs enter from the throat & infect the middle ear. Fluid often persists for weeks after the germs are killed.