Breakthrough bleeding

I've been on the pill for about 9 months now. It's the first pill I've ever been on. For the past 4 months I've been having light spotting the week before my sugar pills (so my third week of active pills) but then an actual period the week of my sugar pills. This month I had an actual period the third week of my active pills and I started my sugar pills yesterday and now it seems the bleeding has stopped. What could be wrong? Is it that I might need a new pill? I also am sexually actively but I've never missed one and take them at the same time every day and use condoms half the time and he always pulls out if we aren't using condoms.