Ear infection will not go away.?

I was diagnosed with Eustachian tube dysfunction about a month ago. I have had 2 ear infections over the last several months. I have currently have an ear infection that started about 2 weeks ago. I had a cold which caused the ear infection. I went to see the doctor who put me on 875 mg Amoxicillin. After around 5 days of treatment the infection got worse. I went back to the doctor who confirmed the infection had gotten worse. She then put on AMOX-CLAV(7 days) and Ciprodex ear drops(10 days). I have one full day of the AMOX-CLAV left and the symptoms in my ear are a little better but still not 100 %. I have also developed a terrible dry cough which I was told could be drainage from my ear. I will go back to the doctor in one week. Has anyone ever had this problem and how did it get fixed?