I found an injured crow in a parking lot. What should I do?

I found a crow rolling around and trying to stand/move in a parking lot. The poor thing seems skinny to me, and I think she may be a fledgling, although my mom says she looks like an adult... Neither of us know much about what fledglings are supposed to look like. She's a girl, and appears to have injured legs or feet, as she doesn't move them, but I did see her move one of them a little a few times... We brought her home, since vets are closed on Sundays, and gave her two jar lids, one with birdseed, and one with water. She ate and drank a little, and we put news paper under her. She seems to be feeling better; she's trying to move around. She can flap one wing for sure; the other, I'm not sure if it's hurt or not, I've seen her open both, but I'm not sure if she's actually flapped the other one. She opened her mouth a few times in the car, but I think it's because she was thirsty. And when we were outside (walking to the door) she made a few very quiet "caw"s, probably to the other crows in our tree. I'm guessing she got hit by a car, just enough to injure her, but not kill her, but I don't know. What should I do with the poor thing?