I have about 2700 affection points with Kira and there hasn't been a dialog yet. I have been in the ship and cantina. I am finished with Taris and about to start with Nar Shadaa.
Is it because I haven't finish Act 1 yet or is it a bug?
She'll have stuff to say after Nar Shaddaa - specifically things that happen after it. Much like the original KOTOR, a lot of companion dialogue requires you to progress the story for it to happen.