i have been having unprotected sex for a year and 3 mths and not on any birth control. starting january my period started to change and came down the first week of the mth, in february it came down the second week, i didnt had sex for a 2 wks, after the two wks my bf and i had sex, and right after we have finish had sex, some blood came down an stopped before night. i took a while to had sex again until march 5 which was before my period date was the 10, it did not came down so i took a pregnancy test and it came out negative. but between these space of time i have gain weight and my breast is started to hurt, it lik when u pulling a straw of hair on your hand, and had some pain below my belly botton....so i was wondering am i pregnant.....?