I don't discuss it, but that is probably more related to being a fairly private person/generational issue. My daughter doesn't have any problem talking about it.
Menstruation is a normal, natural part of life. There really isn't any real reason to make it a secret, except that males find it to be "yucky". She might just be very down-to-earth, and looking for a mature guy that can handle normal bodily functions.
Relax... I'll need some information first. Just the basic facts - can you show me where it hurts?