Is this blue normal on a duck's wing?

[Little Cute Lily]

My Khaki Campbell, Alfalfa, is 1.5 years old and has started molting her wing feathers for the first time. She gives a little flap and 4 feathers will fall off, which is supposedly normal (I'm a first time duck owner, had her since she was an egg). However, I noticed the beginning of her wings are blue. They definitely weren't blue before. I'm hoping someone can shed light if this is a concern or a normal part of molting. I attached 3 pictures.
Also she just took a bath when these pictures were taken.

 

[Earthdale]

Are the quills blue? I can't really see.

 

[Earthdale]

Four feathers a shake seems a bit much.

 

[cheezenkwackers]

That looks normal to me.

 

[Miss Lydia]

I think so too!