If she’s been smiling at you she probably likes you. And that’s good that she doesn’t ignore your stutter, but rather she encourages you to speak more. This is good because she recognizes that you stutter and is open to talking about it. The more you talk about your stuttering around her, probably the more comfortable you will be around her, because she will get to know about the different factors of your stuttering and when it happens so she isn’t surprised when it does