That's normal for their first eggs and they are usually smaller than they will be too. Congrats on the new layer.
Its def one of the EE's from you. Naturally she willbuse the same box as the other 2 that are lating so will take some time tonfigure which, but i knew someone was close. Have a good feeling ti was zoey that laid...but we will see!
And yes it should get bigger. First egg was comprableto the yokie eggs, so all should be going well! Now for the egg barrage!