How long does breakthrough bleeding usually last for LoSeasonique BC?

I started this BC a month and 24 days ago. I started spotting about 2 or 3 weeks in and I am still spotting. Why wont it stop. Should it stop after my 3rd month? This is my very first BC. I got on it for the pain and as a just in case method. And as far as the pain goes there's almost none. An occasional cramp every now and then but its barely painful. Thank goodness. The Spotting is kind of worrying me though.