I've been taking Diane 21 for some years, and had protected (condom, but did not check it afterward), this was march 9, day 19 of my cycle and I'm regular 28/19 days. March 14 i see a drop of blood (mini), this day was also my second in the 7 days rest of Dianne. Now my periord hasent come, is there any real chance of being pregnant?