Yes they are not like some Parrots and certainly the pupils dilate at a very rapid rate with emotions.
Where some birds pin when they are giving you the evil eye.
So I feel what you are seeing is her love for you.
Aaah!! Thanks so much for this info - I always thought pinning was a sign of aggression, so I was nervous when my bird started that up . . . then I noticed him putting his head down and muttering "good boy". Turns out he didn't want to take a chunk out of me, he just wanted head scritches!
I get confused by the pinning also, but in the case of our boy...it is more likely to be aggression and caution towards me. He doesn't pin with my partner at all but depending on his mood he will pin at me. Who would think that a bird can tell you so much with their eyes!