You could have a bad cold or allergies that are turning into an ear infection, bronchitis or sinus infection. Both of them can cause the coughing, sneezing and runny nose. The mucus from either can cause the lack of appetite. A cold or allergy attack that worsens can easily lead to infection which can cause fever. Fluid in the ear can cause the hearing loss...
Sounds like you need to get to a doctor and get this under control before it becomes even worse. In the meantime you can try over the counter allergy or cold medicine to alleviate your symptoms.