I have had my chickens for about 2 months now. They were about 1 yr. when we purchased them. My L.B. has been my steady layer with just about 1 egg per day (on average). She laid a weird egg last week smaller and the shell was very thin (it broke when I picked it up). It has been 5 days now since she last laid an egg. She seems to be healthy (eating, drinking and doing chicken things). Should I be worried? What possibly could be going on with her?