How long does a mated hen lay fertile eggs after rooster is gone?

[featherbaby]

I have a new splash silkie who has been in a pen with a rooster until I got her yesterday. How long will her eggs be fertile?

Also, how long does a fertilized egg stay good if she is not sitting on it? Does a hen go broody after she lays one or more eggs or does she go broody first before laying her eggs? In other words: Which comes first the broody or the egg?

 

[Opa]

Up to about 3 weeks