More pics - gender still a mystery!!

I still am uncertain of my Bourke Parakeet's gender. The females do not have any or have a 'muddy' blue on their forehead whereas the males have a band of blue that is more distinct. My parakeet (Ruby Rae) does have blue, but I'm not sure if it is clearly marked enough to indicate a male for certain. I'll just call him 'he' for simplicity until I know for sure...

So I am wondering about behavior to give some clues. It's now been one week that I've had him, and here are 2 things that I've observed. Does this indicate male or female to anyone?

1. A couple times a day, I've seen him crouch low on a perch, slightly lift his backside, and chatter/warble away. I can't tell if he's scolding or trying to call me in?

2. Today he tried to toss all his birdseed out of his cup and sit in it. Seemed a bit like nest making behavior? He spend about 30 min industrially throwing out seed and circling around before he lost interest and flew off to preen and observe the mess with satisfaction.

Thoughts? Here he is in the seed looking very pleased with himself.

I would suggest doing a diy dna test and sent it to Avian Services Center: DNA sexing and disease testing for all species of birds.
Its only about 20.00 and they send you the test for free.

I bought an Alexandrian, the pet store said it was a he, no doubt about it. I had a dna test done, its a she. Its the only way to know for sure, 100%.