The manga style works lovely on two levels here. First off the half toning and patterning for most of the shading works beautifully. It starts things off with the expectation of a mood piece. Of course it's a bit plus that you did it so well, especially her voice trailing off and her eyes down turned (darkened). Then GULP, she takes back down what she was about to say to the one stallion she's known and been friendly with for ever so long. It makes sense she'd have a crush on him, and while he's happy to see her there doesn't seem to be any reciprocations of those feelings. Perhaps that's why she can't bear to say anything, since the hope itself is so precious that to lose even that would be crushing.
Yet in the final panel as she sits "slumped" on her stool she looks lost in her introspection, probably staying perfectly still as she beats herself up on the inside. Poor thing.
I can understand that one may think that, but judging from the fact that it seems like she wants to say something to Joe but "gulps" it back down, my guess would be that her problem is that she cant tell him about her love because she believes he doesnt feel the same way. She is probably scared that if she were to ever confessed she would be let down.