The "white" that you saw sticking out was her ovipositor. Males have one too but it's a bit more pointed, for spraying the sperm over the eggs. The female's is more tube-like.
Brookster, this will be just in front of the anal fin.
I've never had a female act like that when laying eggs. I've only had males act like that and then a few days later they were dead. No idea why. Water was pristine, pH was fine, no new additions to the tank.
My females when they start to spawn are evil little snots. They bully their male until he's right there beside them, they scoot over a spot, drop an egg, dart after the male, drop another egg, he follows behind. You know who wears the fins in their relationships...