I have had a 28 day cycle for the last 6 months. Regular to the day and even the time of day. I started feeling pregnancy symptoms about a week and a half ago. Nausea, headaches, heavy sore breasts, darker areoles, cramping off and on for 2 weeks, andlower back pain. I'm on day 33 of my cycle now. I had a negative test the day of my missed period, yesterday on the third, and today on the fourth. All negative. Yet no period and no positive hpt. With my last pregnancy I tested positive 2 days before my missed period.