My period should begin tomorrow, i don't have any symptoms showing i may start. Just this morning my nipple started hurting really bad, for the past two weeks I've been cramping very mild but i can feel it and passions sometimes in my sides. I had sex, unprotected, during my fertile window three days from my ovulation date. If i ovulated later then what my tracker said, could i still be pregnant? I also just took a pregnancy test yesterday that came out negative. Is it to soon? When can i test?