Female Finch is not as active

Question
I have 2 female finches in the same cage, they fixed up a nice little nest in their hooded woven nest, I have noticed one of them has puffed up a bit and not as active she looks fat, keep in mind I purchased them about 2weeks ago they couldn't tell me nothing at the pet store when purchased. They were sleeping in the nest together now 1 is perched on top, the one inside is the one in question, she sat yesterday when her head in her feathers or just her eyes shut and I noticed her breathing was different. How do I know if she is trying to lay an egg? and if so how long should I wait to suspect egg binding?

Answer
Hi Wendy,
you'll recognize egg binding by the female looking fluffed up,and panting,usually sitting on the floor of the cage,or sitting with her wings hanging down.  You'll also see her pushing.
 If this behaviour doesn't clear up within 6 hours you can usually suspect egg binding. Good luck,you can go to egg binding sites on the web and find more info on treating them...Elizabeth