Bumping into someone while walking was originally just a trivial matter in Dorothy's eyes, merely an occasion for an apology, and essentially resolved, provided it wasn't a confrontation with someone looking for trouble or an actual injury caused. Otherwise, most normal people wouldn't keep harping on about it.
Though her new clothes were now dirty, this was no big deal for a witch; a simple cleaning curse would restore them to new. And after all, it was an accident with a child, a cute Little Lolita, not some unruly brat.
Besides, she was actually to blame for not watching where she was going, her gaze wandering all over the place. She had her part in it, so it wasn't entirely the other party's fault.
Therefore, Dorothy hadn't planned on making a fuss and was ready to bend down to help that Little Lolita up and comfort the adorable little bunny.