How old are my bantams?

[Jjdesmo11]

Is it too early to sex these bantams. I have figured out the breeds but I’m in doubt that combs won’t start popping up soon. I have 5 total. The first picture is a straight comb golden sebright who is looking roo-ish. The others I think pullets. Probably around 4 weeks? So may be too soon to tell. Thanks.

 

[Rock17]

1 is male (i think)