I have a hen who began laying around the beginning of July. Her eggs have been increasing in size (up to about 45 g) until several days ago when the eggs began getting smaller. For the last two days, she has laid tiny eggs of about 20 g. I broke open the egg from three days ago (25 g), and it was basically all yolk with hardly any white. Should I do something? Does this happen occasionally, and she'll go back to normal soon?