Hey Liz,
I *SO* agree about the sound level of cinemas. Who set that, a stone deaf person? Certainly couldn't have been a normal human being.
I have a girlfriend who also has a strange condition (not RSD) and we try to get to a movie once every, maybe couple of months. We've cracked the problems, we wear ear plugs. Started off with the softer ones, but quickly switched to industrial strength...and that's fine. Still a little loud, LOL...
You are not alone,
all the best