Papilio machaon

Hello, i've got my Papilio machaon in my greenhouse.
But, the male is doing strange last days.
There is a female in the greenhouse too, and when she is eating he's going to fly around her, than she moves her wings just like she is flying, but she stays on the flower, pushes her body up, and walks little rounds on the flowers ( Lantana ).
I though this was a matingsdance or so.. But when the male starts to fly around her he makes big circles around her, and evru time he comes closer, i was think, when he was really close that he would mate her, but that he starts to eat...

What is it?

She is 2 days old, not mated yet.
What sign will she give when she does want to mate?

Today, the male did not fly around the female, but soon i noticed that she was laying eggs.
So, they have mated out of theirselves!