My boyfriend and I had sex about a month ago, and I should of started my period oct. 10th. But I didnt. I never even had the cramps or anything, and I got this gross brown stuff on my panties. That lasted around 4 days or so and wasnt enough to wear a pad. Was that my period or is that a sign of pregnancy? I have had some symptoms like headachs and dizziness along with using the bathroom like every two hours. I did take a home pregnancy test with my first pee but it said negative. Im so confused please help!