no worries
I did my first class 1 med this week and was worried about the hearing test. I played drums for 15years and played in a heavy rock band for 4/5 years. I expected that I would have probs. especially at the high frequencies. HOWEVER, I only missed one!
The sounds are barely audible, and all I could hear was my heart and breath. So I held my breath as much as possible so as to better listen. It all went well and I can hear just fine, but I understand your concerns. I guess what I am trying to say is that unless you specifically know of hearing loss in yourself, you may be worrying too soon, like I was? Bruce Dickinson from Iron Maiden passed his and he must have been affected by all those years on stage...
Hope it goes well for you
KB