Can Muffled Hearing, Variable Hearing Volume Be Due To Ear Damage?

hello - I was recently assalted by a woman in the street, she punched me in the left temple and right in the left ear, quite hard - I went to hospital and they said there was redness in the ear, but didn't appear to be damaged to the eardrum - however aprox 4 weeks later, I still notice a change in my hearing - sometimes me hearing suddenly feels 'muffled' or seems to vary in volume for no reason - I am scared some damage has been done - is this likely, and is it possible for a doctor to test if damage has been done to inner ear etc.

Many thanks for your help