Probably one of them was using the nest box while another just couldn't wait to lay her egg - not uncommon with young birds and also smaller 'pullet's eggs' are not uncommon early on. On the farm we'd pack them separately and sell them a bit cheaper - they were often bought for pickling.
Your chickens were probably thirsty this morning, it was quite warm yesterday and again it got warm this morning - if you can't let them out very early can you arrange for them to have some water in their coop?
Also if one had it's feathers fluffed out it could be that she was overheating and needed to cool down - is their coop in the sun? It might be that it gets a bit hot in there now that the sun is up early in the morning - can you fix some shade over it or some extra ventilation.