I'd say the chances are pretty high that she likes you. Unless she's just strange that way or something. Does she behave at all strangely with other people.
I had an older woman who used to do something similar to me at work. I found it flattering and just flirted back with her. Maybe you should try it and see what happens.
Edit - On the other hand, this woman who did that to me was someone I already knew well when it started. It wasn't like she started doing it out of the blue. I think she kind of knew I'd be OK with it. It almost sounds like the one in your case is taunting your or something. In which case, it wouldn't be very nice. Are you sure she doesn't like you?
she has done similar things to others but it's not nearly to the extent that she does to me.
i really don't think flirting is a good idea since i don't really have any experience w/ flirting and would probably make idiot of myself and also if she really is just doing this just for her amusement then i'd really look like a fool.