Do you like her, and want to try dating her? She's made the opportunity for you to follow-up, so~ if you want to try, why don't you ask her "will you be doing anything after the 23rd?" and see if she replies. If she does, maybe ask her if she wants to hang out or do anything together.
If she doesn't reply after that, then you could easily assume she's not interested in spending time with you. In the end, I don't think you really lose anything by asking. Could always play it off as just wanting to hang out as "friends" or w/e because haven't seen each other in a long time.
It depends on the girl... so you said she's shy, so might have asked out of curiosity because she's been wondering about you. And if she's really that shy, she may be waiting for you to make the first move to re-connect.