period or plan B?

A`Lonie
Hey guys so about 2 weeks ago me and my boyfriend had sex, the condom broke and we realized it too late . I took Plan B the day after . About 3 to 4 days later I saw what I though was spotting , considering that's a side effect. It wouldn't stop and it turned out to be more like a period. I know this is going to be a little TMI but I know my body , I was having period cramps & period mood swings . Normally when I get my period and I wear a pad I can feel the blood actually come out . I was also feeling that . This lasted all up until today . Was this my period or a side effect? I also took a pregnancy test Sunday ( today is Tuesday ) and it was negative. So was this my period? And could I still be pregnant?