I'm really not sure where you get the information that women are generally introverted. Just the same men are not generally any certain way either. My proof is in that all the women I've been with are more extroverted than I ever will be.

From all the details though, it's really hard to say whether she's interested or just being friendly or polite. Your interpretation that she seems 'irritated' could be perception or otherwise.

I don't know, though at this point if she's not willing to make small talk that could be a sign she's keeping it at the acquaintance level but none of this is cut and dry.