Cosmos Ladybird

Guernsey Donkey2

I have grown some of these Cosmos Ladybird seeds and now realize that I should have taken a photo of them. They are a Thompson & Morgan seed. The seedlings are about 3 inches tall now but are turning from green and healthy to yellowy green and the leaves seem to be turning in on themselves. Has anyone else grown these - successfully or with the same problem - I will give them another week or so and if unsure may remove them  and use other seedlings in their place.