Do you have a picture of her full body? Even seramas, being a popular pet breed, can get dumped when people end up with too many due to irresponsible breeding and things like that. :( I’m very glad you saved her. Tame chickens can accept a person as their flock, just like doves and parrots, and...
I’ve never had a hen attack me, the worse that’s happened has been a bantam broody who pecked me when I reached into her nest. That didn’t even hurt. I don’t think it’s normal for a hen to attack a person, even if she considers them part of her flock.