i started my last period march 26. I was due for it April 25, I usually have 30-31 day cycles. I never got my period. I had sex March 10th, April 25,26, and may 3rd. Today is May 4th and i started having cramps this morning with some brown and now pinkish/red discharge not enough to fill a tampon or pad its mostly just when i wipe is this my period being late or could it be implantation. I took a preg test urine today and it was negative?