What's happening?!

Allison
SO 
I'm on the pill and have been for quite a few years.  USUALLY it causes me to stop getting my period all together which is perfectly fine. I've even discussed it with my doctor and she says that's totally normal. If I ever do get my period I just spit for a couple of days and that's it.
BUT I literally have been on my period since the first of this month.. Maybe earlier, (I don't really keep track because I never usually have one to track). It's been heavy flow, sore breasts, and horrible cramps the entire time!! WTF? Has this happened to anyone else?