So I've been on birth control for over a year now, and I'm aware that while on birth control you can skip your period if you continue onto the next pack when the 4th week starts. This past month I elected to do this, but no I do not frequently. I have only done this once before and everything went fine. This time though my period started the following week instead. Now, a week and half later, it's still going on. It's very light and the brown blood rather than red. I understand spotting is usual and nothing to worry about, but it concerns me that this has gone on so long, particularly since I'm on the pill.