Congratulations @NancyNurseCxMama. Different shape (and likely a different shade of brown) almost certainly means a different girl started up. I've not found a particular breed lays a specific shape. Seems to be by the individual chicken. For example one of my White Rocks lays a "usual" shaped egg, fatter on one end, more narrow on the other. The other WR lays a egg that is almost impossible to tell which is the "fat" end.