My kids are big LOTR fans. We were riding our horses in Kennesaw Battlefield Park on New Year's Day, and my daughter stood up in her stirrups and repeated King Theoden's speech word for word. Then all of us charged over the hill, stirrup to stirrup.
The hikers on the path looked at us like we were nuts. (Maybe we were, but we were happy nuts. :-D )
I sat next to three teen-age boys my second trip to see ROTK. I knew, of course, what was coming when the Rohirrim appeared on the hill. These boys were whispering on the edge of their seats and I didn't mind at all. During the charge, all three boys were still on the edge of their seats leaning forward and one was pumping his fist in the air:-)
Maybe young people, (at least some of them) are closer to these emotions than adults.
Continue to have fun. Your daughter has heart.