Better pictures would be helpful. There is no way to tell gender by that pic. Try getting one from the side. Also, does she still cheep like a young duckling? Or is she loudly quacking or making a sort of rasping noise?
Looks like a Muscovy. Also, since it seems she has most of her adult feathers in but still cheeping, I would say around 1-2months. Keep listening to her voice, it should change soon. If it is a loud quacking, its a girl. If it sounds like a low, raspy sound its a boy.