What are some things that children worry about quietly, and we adults have no IDEA they're worried about it?

Yesterday my daughter, Corrie, and I took her 9 year old, Brande, to a camp at Kaw lake. She’s been beside herself with excitement for about 4 weeks. Long story short, we got to the lake OK, but going in and actually finding the CAMP involved about 45 minutes of going down wrong trails, turning around, back tracking, going another way, turning around and going back the first way in case there was something we missed….finally got some directions and made it there (after only having to turn around one last time and go back a bit.)
When we saw the cabins we said, “THERE it is!”
We didn’t realize that Brande, who is usually a chatterbox, had gone very quiet over the last 45 minutes until she leaned forward from the back seat and said, “My stomach was starting to hurt because I didn’t think we would find it.”
Awww. Poor baby! :( Sniff.