Hi, Banties are notorious for broodiness and I feel that they are one of the best mums in the chickenworld.
She is young, however if she is broody you could put some eggs under her, say 5 eggs.
She will sit happily and she will get out when she needs to to eat and drink and toilet.
I have 3 broody banties at present with all of them happy to sit for 3 days before they want to get out of their nursery pens to scratch around. I have feed and water in there but they dont want it until they are ready to get out.
Now if you get really concerned for her and she stays sitting for too long by all means gently lift her off and put her out to feed etc, she will snap out of it and feed , then go back to nest.
When they hatch, you may end up with a rooster, however he wont be a problem until he crows in about 2 months.
I think you would love to watch your banty with her chicks, its wonderful .
Good luck, let us know how you go!
Helen