My fiancé and I had sex on the night of the 13th of February. The 14th that morning we bought an off brand of plan b. I took it approximately 12hrs after intercourse. Three-four days later I began to spot then heavy bleed. My period wasn't supposed to come till 2 weeks later. I have been bleeding heavy for about 7 days and light for an additional 4. I havr been bleeding for 11 days. Could this be a mixture of stress and the plan b pill? I have taken plan b twice before in the past two years and have not had symptoms like this. I do not have any other symptoms except the excessive bleeding.