It's a weird kind of melancholy, isn't it? Yes, you're relieved to be out of a position for which you were ill-suited and, honestly, made you miserable anyway. However, it still hurts a bit to have to acknowledge to yourself that you were simply not good enough for that particular job. Beepatrice is definitely experiencing those mixed feelings today. In her case, the degree to which it is preying on her mind is demonstrated by the fact that she forgot to introduce herself; she just wandered over to the window and started monologuing!
I'm thinking about Brun's words in the last panel. I'm not sure that her question is negative but, rather, that it may be hopeful. Just how many new people are going to wander in and what strange new things is she going to see? To be a good bartender one must, after all, have a high tolerance for new and strange people and, indeed, to enjoy people-watching.
Meanwhile, Millifeulle's reaction suggests that Beepatrice has made her slightly embarrassed of her species!