What to do if the running doctor in the hospital misdiagnosed the disease due to some disturbances.?

The thing is that i had taken my DD(15month old) to hospital coz of regular ear tugging and itching. It was the running doctor that would check my dd for it was not a regular schedule appointment.Before my turn came the doctor had a discussion with the former patient and was not in a good mood from what i observed and the Dr. now checked my dd and told that everything is fine. just apply some lotion it will be fine but i was not satisfied but had to wait for the regular appointment. And regularly i tried the lotion but it didn't go so i tried to shine a good source of light into the ear and there i could see a growth of tissue on the c very deep now i am so worried and want to complain about the doctor not diagnosing the disease properly what should i do, any suggestion could be appreciated.