Hens delay incubation of the first eggs so that the entire clutch hatches at the same time. She might have had another egg and that's why she wasn't on them yet. If she has been bred, there are likely marks on her back from the rooster(s) mounting her. If she doesn't have missing feathers, she probably hasn't been bred. If they're fertile eggs, some people swear they're a great aphrodisiac. You can basically do what you want with the eggs, just don't plan on keeping any more little boys if you incubate them. You might be able to get away with them surviving as it's some crazy thing that chicken eggs can do. They're basically in limbo and generally survive until incubated.