An ear infection
deserves both evaluation and treatment. As you suggest, hearing can be effected, and therefore I would recommend evaluation by your daughter's pediatrician
Ear infections come in two types: otitis media and otitis externa. Otitis media is inflammation of the middle ear (such as the tympanic membrane or ear drum) which is the most common reason for a child sick visit. It often causes ear pain
and fever. Normally, no abnormality is visible with the naked eye. While fungal infections can cause this rarely, it is far, far more likely to be a bacteria. Antibiotics are required to treat this. It is unlikely your child has this.
Otits externa is inflammation of the auditory canal. This is also mainly is caused by bacteria as well, but fungus can cause ~10% of these infections. This infection can be seen by just looking in the ear. Itching, discomfort, and change in hearing can be symptoms. Often pain will be drastically increased with moving the ear. To treat this, cleaning the ear thoroughly (by a pediatrician) is the most important. After that, anti-fungal ear drops can be prescribed. Occasionally, steroid drops are needed and rarely anti-fungal pills are needed. Keep in mind, other skin conditions and bacterial infections can look similar.
If left untreated then, hearing damage can occur as can invasion into the skull bone and even a brain infection! I therefore recommend you see your daughter's pediatrician.