There's a hard pack behind the back of the ear. What's going on?

A hard pack grows behind the back of the ear. The common cause is swollen lymph nodes caused by lymphadenitis behind the ear. It may not be accompanied by any symptoms, and it may also be accompanied by pain. The most common causes are colds, otitis media or rhinitis. Suggestions: You can go to the hospital. If it is an inflammatory infection, you can take antibiotics orally for treatment.