Is it the standard contraceptive pill? Or the mini-pill? As far as I know it's more important with the mini-pill that it be taken at the same time everyday. With the other contraceptive pill (and I totally don't have the correct terminology, sorry!) there is a little bit more leeway. Have you had a look at the enclosed information sheet?

It could also still be your body adjusting to being on the pill? It took a few friends of mine a few months to adjust when they started on a new pill, and one friend had to change pills because she kept having breakthrough bleeding. I don't have much information, but hope you're not pg! Goodluck.

(I just realised my post isn't particularly helpful at all...but I'm thinking of you!)