What's not going right

[TheDuckGuy]

I have two ducks male and female they're 7 months old and my female just laid her first egg about a week and a half ago and then another two days after that I did in fact crack open the first egg to see if it was fertile and it was but since then she hasn't laid and won't let my male mate her she just runs away

 

[nuthatched]

Its still early in the year for laying, plus she's still new to laying so it won't be everyday yet.
You need a few more female ducks for your drake and don't incubate the eggs until your duckhen has been laying awhile.