I've been dealing with the place i got her from for years, i know how well they take care of their animals, i would be incredibly surprised if the mites came from the snake. But the only reason i say from the mouse is because i got it from petco, and not a privately owned place. And as far as the shot... it was $16, and it's better safe than sorry as far as i'm concerned. So say i see more mites on her in a few days... what would i do then?