I started tri-sprintec 3 1/2 weeks ago and now have my period for the 2nd time since i began it. The first time was a week after finishing my last normal period. Went 2 days without it and now have it again. The last period was 9 days, very heavy and lots of cramping. So far this one is the same. Is there a difference between these pills? Should I be concerned? My doctor suggested I stick with it for 2 more months to see if it becomes more regulated but this is really miserable. Can you help?