Weird bird behaviour...

[Murr44]

Does anyone here have a budgie? I'm asking because I couldn't find any information about this. My friend has a male budgie named Sky & the other day when I was over there this loopy bird did the strangest thing. He hopped on my finger & started nibbling on it (I've seen him do that many times so it's not unusual). Here comes the weird part; he suddenly squatted down on my hand, leaned forward with his head feathers puffed up & his tail feathers puffed up too. While he was doing this his pupils contracted to pinpoints & he allowed me to stroke his back. This went on for about 2 minutes and then he seemed to snap out of it; as if he was in a trance. I read on several budgie pages that they don't like their backs stroked and that puffing up their feathers was their way of showing off. That's about all I can find out about it though.

Just asking if anyone has ever seen this behaviour before...