Found in the coop, very soft, filled with fluid but has a sort of rough texture to it. Don't know who left it there, have three girls who hatched mid October, wondered if one of them was starting to form eggs. Found it a few days ago but no new proper eggs since.
Yes, it's a first egg, although a weird one. You get all sorts of weird eggs when their assembly line starts up. Hopefully soon you'll get your first USEABLE egg.