2-3 of my hens have been sounding high pitched for a few weeks now. I don't wish to automatically assume they're sick like ive done in the past. I much rather breathe and take things so this time. I don't notice any of them sick. Everyone is eating and drinking (at least from what im trying to study) nothing unusual to add on to my anxiety. is this normal? If is a stress thing, what can I do to fix this? they all have space, feed, clean, water, clean nesting boxes all the necessities needed.