How do you know if you miscarried, it you're not even sure if you were pregnant to begin with?

You weren't pregnant. What you saw was just a piece of uterine tissue you'd ped. The Seasonique prevented any conception. The other people who replied are just confused. The reason you didn't get your period for 3 months was the Seasonique, working exactly as it is designed to work. And a pill doesn't cause you to "abort the baby". It prevents conception and implantation, and it does so at such an early stage that everything is happening at the microscopic level. The symptoms you describe are those of a stomach flu or maybe food poisoning.