Ok, no male no worries

Candeling is a usefull technique. Get a bright flashlight, hold the egg up and position it so the beam shines right under the egg so you can see the contents inside.

If the egg is fertile, you will see a dot (which would be the embryo's eye) and some bloodvessels spidering out like vines in the egg. It's best to wait a few days before candeling them because sometimes you can't see anything right away. If the egg is unfertile, you will be able to clearly distinquish between the yolk and the white of the egg.