Hello, Tonight My Daughter Age 16 Was Playing The Drums

Hello, tonight my daughter age 16 was playing the drums at church with headsets on. She listens to the music track as she plays the drums...she had the headset volume all the way up.... All of a sudden there was an extremely loud pop sound that lasted for several seconds.... She removed the headset... And experienced a burning sensation in both her ears.... She is not hurting but she is not able to hear very well... Sounds are muffled....hoping her hearing will improve over the next few hours. What are your thoughts?