I took my pill late, started bleeding and haven't stopped!

I'm 20 years old and on the pill Yaz. I've been on it since July. About a week before my period was to start on my last pack I took my pill 2 and a half hours late and thus started spotting the next day. I kept taking that pack until the pink pills were done and then tried to skip last period by starting a new pack immediately following. It is now three weeks since the late pill and I'm still spotting pretty hard core. What's happening???