I have taken birth control for a year, and i just recently switched to a higher doseage, and it was the same brand, and i am at the end of this month on the new doseage and i have a period but it is very very light and it has been that way for 3 days, and now it seems as if Im not even on it or bleeding, I was sexually active this month and did have unprotected sex, what does this mean? Is it normal? The brand of bc is Microgestin