Black spots on crown! Pic included

[tinytina]

I noticed some black spots on the crowns of some of my chicks, they are just over 3 weeks old. Should I be worried?

Chick 1

Chick 2

While we are at it. Can anyone tell if they are boys or girls? Or is it still too early?

Thanks!!!

 

[KellyHM]

Looks like it got pecked by the other chicks or scratched its comb...no big deal. And I'd guess boy!