I have four chickens (a buff orpington, a blue ameraucana, a barred rock, and a cinnamon queen - no roosters) and today when I went out to collect the eggs there was only one and it was very tiny. We live in Texas and it went down to freezing last night, but we covered the coop very well, and made sure they had plenty of food and water. We got them in April of 2016, and they've been laying for around 4 months. I've never seen any of their eggs this small (a little larger than the top notch of one's thumb) even when they first started laying. It looked a bit like the orpington's eggs in color, but I could be wrong. Any ideas what could be up?