Comb changing colors??

[Watermeat]

One of my girls has a comb that changes it's color multiple times a day. It can go from bright red, dull red, and bright and dull orange. It seems very unusual to me, since none of the other hens have this issue. I knew I had to post a forum after watching it turn from a bright red to a pale yellow-orange in no more than fifteen seconds.

I'm not sure if this is something serious or not, but I didn't want to just ignore it in case it happened to be a big deal. She's an Easter Egger and also suffers from wry neck, in case this is important information.

 

[RhodeIslandRed5]

I have a chick whose face stays mostly red, and I'll see her face flush pale every now and then, but most of the time it stays red like sunburn. She'll also pant when the others don't inside the house. Makes me wonder what's wrong.