She may not have done it on purpose, intending to hurt you. Sometimes I get scratched when I pick up a chicken because they feel a little off balance or possibly feel threatened and so they thrash about a bit. You have to remember that they are prey animals, and in their world anything that picks them up usually intends to eat them. They are not like most cats that just go limp when you pick them up.
Treats and time will calm them down…it’s a good sign they have good predator instincts! Keeps them safer 
That is a good way of looking at it. Seems it's always the tamest, most favorite chicken that's the first to go in a predator attack. I think it's because they're tame, and less wary.All of mine hide every time I add new shavings to their coop, and act like the shavings have come to murder them. They are skittish after that and run from me for the next day or two because I brought the murderous pine shavings to their safe space!
