A hen has certain triggers that cause her to release a yolk to start the egg through the hen’s internal egg making factory. That journey is somewhere around 25 hours but that can vary some. One of those triggers is daylight. If it is getting too close to sunset that trigger should stop her from starting an egg that has to be laid at night.
But you don’t have a hen, you have a pullet just starting to lay. While most pullets get it right from the start, the hen’s internal egg making factory is fairly complicated. It’s not that unusual for a pullet to have to debug her system. One of those kinks might be when she starts an egg. Often they will lay those eggs from the roost. At least yours made it to a nest. It’s also not unusual to see thin-shelled or no-shelled eggs, eggs with extremely thick shells, double yolkers, no yolkers, no whites, or just plain weird eggs. What’s remarkable to me is that so many actually get it right to start with.
Just be patient. She should get her system debugged pretty soon.