Kaki Campbell started laying greenish eggs weird green color in pen

[hayleyasaurus]

Hi! My Kaki Campbell duck recently started laying eggs with bright green coloring on them. I also noticed the same green color in the pen. I think is discharge from when she’s laying the egg maybe. Is this normal or should I be concerned?
thank you!
Hayley

 

[hayleyasaurus]

Also I believe it’s the end of the egg lying season, but her laying has been weird lately. She’s been laying at more random times of the day and have seen her outside trying the lay eggs. She used to always lay them overnight in the duck pen. I add oyster shell to her food and the eggs are nice and strong.