I Have Used The Metro Gel Days Before My Period....so

I have used the metro gel days before my period....so now I should have gotten it because it's passed my due date already now, but all I get is just a little light red discharge in the morning then it goes away..... I usually get my period less then 28 days... And my breast also have been a Lil painful for almost 2 weeks now...I did a pregnancy test and it was negative. ....is this caused by the metro gel?