She probably pooped!
Yes, I think that's normal fluctuation. Just as we fluctuate, so do the snakes. It's when you start to see a pattern of it over weeks/months that it becomes an issue.
What are the dimensions of the T8? I have a divided PVC vive myself, but not the same brand. Perhaps you can order them divided, or can put in your own divider -- just make sure to secure it all around with silicon or something similar, absolutely no holes, and let it air out even beyond what is advised on the product label.