Is my chickem okay? I think she breathes weird

I went to close the coop this evening and she was in the low sitting place instead of on the higher sitting place where she usually sits with the other chickens. Then I noticed she was breathing weird. Any tips on what to do? This happened today and I have no knowledge of her breathing weird on any other days.

However, either her or my other buff orpington have been producing white-ish eggs with a very thin shell, instead of eggs with a normal cream color for about 3 days now. Could that be connected?? I assume low calcium or such.

It should probably also be said that she is the lowest on the pecking order and very timid & easily scared, so she often stays away from the rest of the flock when I give out snacks (and I assume otherwise too).

Apologies for my bad English, it ain't my first language :')