Those eggs were doubtless under development before she was moved. Being with pullets is pretty disturbing for her. When she is settled--probably not too long, she will lay again. Moving a hen is pretty traumatic for them, new companions are not friends. Patience. Mixing any new birds, any age, especially differents breeds and/or ages of birds, is not always an easy task. And yes, a change of feed can also interrupt laying. Grower won't hurt a bit ( I feed medicated Starter to my chicks, until the pullets begin to lay-about 4 1/2 months, then mix Layer Ration with Starter for a week or so. ) Have separate pens for age groups, no mix of ages or hatches. There are various ways to help them adjust to mixing.....I just rarely do it at all.... Good luck