Getting photos may help.
How is she behaving? Is she lying down, squatting, tilting her body, panting, acting normal or not?
One of my turkey hens always wanted to fight the roosters during her laying periods, and every single egg she lay looked normal until you shone a torch through it, which revealed each egg had at least four separate star fracture impact damage points. They were fine enough to lay, but when she tried to brood them all broke. This happened for a few laying seasons, or more to the point a very prolonged one since when she couldn't brood she merely started laying again... Anyway my point is if she's been kicked hard or attacked or even had the male try to mount her as she lays an egg, or tries to brood, or if she's fallen or landed wrong or whatever, you could be seeing a smashed egg's results. Which are often fatal, especially if you're seeing blood.
A bit more info would help us tell what's what. Best wishes.