My hen is acting weird?

My four year old Speckled Sussex has been acting weird recently. (For a few months apparently, I've only noticed it in the past month) She will make weird noises randomly (especially the one they make when they see a predator), like when we go near her, or she'll make broody noises (even though she's not broody) and she'll poof out her feathers. I used to hold her on my lap every night since she was a baby chick so I don't think she's scared of people, so I don't know what it could be. Tonight I called her over because I had a grasshopper and she came running, making broody noises as she came up, and then she ate it, and another chicken came up behind her and she made one of her predator screech noises, then went to perch, poofing up as she did so. Also I was sitting with her, petting her, and she made this really long whistle like noise (like when they're going to sleep) and I continued petting her and she made purring noises. So I don't know what's going on with her, my mom thinks maybe she's getting ornery in her old age. I just want to make sure nothing is wrong with her..