what's a reality check?
Foster parents have usually seen most things so I doubt they think you are that odd, it's not worth hurting yourself over anyway.
It's okay that you were excited! We're all excited about new experiences. They were probably shocked that you hadn't ever had the opportunity to see Santa Claus before, which is unusual for someone of your age. Never mind that though, just enjoy that you were able to feel excitement! I wish a special Christmas season.