Yeah, the blushing was great. Her reactions overall were very well done.
I really wonder how you will do portraying her now, as she's supposed to act younger, or actually, act her age, in the next chapter, if I've remember it well.
By the way, I noticed you clearly stated her being thirteen, while from having read it when you did chapter one I had noticed her age actually wasn't stated. I thought of her as being fourteen. ^^
Can't wait to see some further regressions, too.