oversized eggs

i h ave a hen who layes her eggs very infreqently and when she does she seems to be in a bit of distress,the egg is the rather larger than a normal egg and at times she has laid a few soft shelled eggs,her breed is a amber. Can anyone help?

When my girls lay a large one, its always a double yoker. They have been laying for a few weeks now, and I havent had a large one for over a week. Is your hen young? Maybe that she is getting into the swing of things? I am VERY MUCH NOT an expert, so someone who knows what they are talking about will probably tell you whats what - just thought I would mention my experience of big eggs!