I was on birth control and skipped my period for 3mon. when it came time to have my 4th it never came till a month later now on it again 2 weeks later?

Low dose: You must be on a very low dose birth control pill. With the low dose, you get effective birth control, but little growth of the lining, so periods tend to be very light and sometimes nonexistent. You can also have breakthrough bleeding, where the lining becomes unstable in the middle of the month and you bleed. If it keeps happening or if you are concerned about the lack of periods, you can change