When I use to take birthcontrol pills my period always started on the third sugar pill, not the first. In regards to how long it takes well at least one month, but you should be using a second precaution anyways since many things will decrease the effectiveness of the pill including drinking liquor-different medications and so forth and the pill isn't 100% to begin with. I personnally don't use the pill because it's useless in my mind condoms and spermicide (foam) together are much more effective (and i'm 25 with no pregnacies as of yet. I can list many pill users who have children along with a few who where on the needle.

I went onto the website for the specific pill that im taking, and it says on there that this pill only takes 7 days to work, if I took my first pill on the first day of my cycle... Which I did. I didn't have sex for the next seven days either.. My one friend said that the same thing happened to her, she didn't start her rag until a couple days later, so im going to wait till about wednesday or so, and then if nothing.. I'll start thinking about what I should be doing next.