Help please!

Stacey
So I am usually on the contraceptive pill, but as me and my boyfriend were arguing I didn't take them while he stayed as his cousins and when we made up we had sex. 3 days later my period came (14th Feb), only lasted 4 days, very light. I was due on 13th of March and still no sign of my period, have had mild cramps here and there but nothing like usual, have had heartburn itchy boobs and discharge but took a test and says negative, could I be or ?  Pleaseeee help!