40 minutes is a long time to boil eggs. When I overcook hardboiled eggs, they do get a greenish tinge around the outside of the yolk. Bad eggs smell very bad and will taste off. Fresh eggs in the refrigerator can keep for up to 5 weeks, so I think yours are probably okay if they taste fine and don't have a rotten egg smell.
Life's a journey, not a destination.
It's easier to stay on plan than to get back on plan.