Seedling slightly yellow after transplant

This is my first experience growing a photoperiod plant. My very first grow was auto's.
So I transplanted this plant yesterday, it's 2 weeks old. It looked so healthy and green but now it is slightly yellow, especially the cotyledons. It's only the day after transplanting it.
Is this normal? Also the plant looks quite small?? (I think)
And the red stem, is that ok?

If that is straight coco you’ll need to give it some nutrients as coco is inert

Darkoh69 said:

If that is straight coco you’ll need to give it some nutrients as coco is inert

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It's just regular soil.