I wouldn't change a thing Shannonmcn. It's all instinctive for Cc. She's a prey animal and her reaction is perfectly normal. It would save her life in the wild. You're seeing this as a reaction to you personally, when it's just reflex for her. The fact that, once she realizes that it's you, she'll come back out and interact with you or just go on as usual just shows she's feels comfortable and safe in her own home. That tube is her bolthole and she knows nothing can get her there. Nothing to worry about.
As for stressing her, all small rodents's lives are somewhat stressful. There really is no way to completely remove it for them. What you describe shouldn't really be harmful to Cc. She forgets it all fairly quickly.