Hello,
I am a new member as well and new to raising chickens.
I have 4 girls and they will be 2 months old this Friday.
I have had the girls since they were 3 days old they are all
different breeds. I too noticed the beaks changes colors,
combs looked light and legs started changing color.
I really don't think there is anything wrong with your babies.
They grow so quickly and every day I can see them changing.
Matter of fact my Barred Rock's comb is fnnally turning a deeper red
as it has been pink. Good Luck with your chicks and yes they are babies!