It wasn't that she couldn't heal herself. It was more that she tended to forget that that was the most logical step to take after falling and cutting oneself. She was simply so used to it by this point that the stinging and bleeding didn't phase her as much. She wasn't six anymore, after all.
"I'm just hoping I didn't manage to ruin the mat." Dora brushed herself off and bent over to pick her wand up off the ground. "Don't worry about it. I think I've got it." With a bit of finagling she started the process of healing the skin over her knee
She ended up on her butt again when she found that she couldn't keep her balance, heal her knee, and reach out for the rock at the same time. She should have known, really. "Lovely," she muttered before looking back up at Cass. "Ignore me. How've you been?"