Lots of birds flirt with being broody. They'll practice for several days, sometimes acting like the classic broody, sometimes they could not care less about those eggs. That's why I always wait and make sure they're dedicated before I set eggs under them. To me, dedicated is at least two nights in a row on the nest, plus all day.
If you're wanting her to be broody, you can bait the nest and see if that helps. I mark eggs and place a decent sized clutch in the nest (usually 6 or so). You can use fake eggs, real eggs, whatever floats your boat. My personal feeling is having that clutch under them helps trigger the hormones.
If you don't want a broody, continue to collect eggs frequently. Take the fake egg from the nest. You may need to resort to a broody buster if she's truly dedicated.
Stem cell transplant from unrelated donor in Feb 2015. Thank you to all my friends here on BYC for all your support during my treatment and ongoing recovery!