hello well i had intercourse with my fiance 2 months ago but on that same months i became on my period.. but this month i havent been on my period.. and i onli had a tiny little blood and brown stuff for onli 2 days and i have so much pain in my stomach and sometimes my nipples get sore... but i done a pregnancy test 2 weeks ago and it came out negative.. so if am not pregnant what else could it be?