Pregnant?

My husband and I are TTC#1. I started with some light brown discharge the day my period was supposed to start. The next morning I passed 2 large blood clots. Then it was 2 more days of light brown spotting. I have nausea, headaches and bloating. I took two early pregnancy tests, both negative, one 4 days after the bleeding started and one a week after the first. Could I still be pregnant even though both tests were negative?