She doesn't even hear that faint sound. The pain is nearly too much. But she has to press on. If she lays down and gives up, her soul gem will eventually be crushed by whatever comes to finish her off. So she has to stand up. She has to continue on. There's no other choice.

She can see Sayaka in the air now, carrying the bloodied Mami. When did that happen? When did Mami get hurt like that? Homura realizes that she may really be out of her depth here. She might really die.

And as if summoned by that thought, the Assassin makes its move. It's the kind of thing she never could have predicted; maybe if she had been uninjured she could have dodged, just maybe. But as she is she's a complete sitting duck. So it slices her easily and she collapses once again. It's pierced her through her belly, and that hurts so much worse than the pole did. Her entire world is hurt and pain and a fevered thought, a desperate chant.

I don't want to die.