When I first started tri-sprintec, I thought once you started your period you had to start a new pack. I've been on it maybe five months now, and usually get my period before I even get to the white pills, so I finish the active pills and start a new pack. This month, I just finished the active yesterday and haven't had my period yet, although I thought I was getting it a few days ago because I was bleeding, but it was light and went away so I don't think it was my period. Should I start my new pack, or take white pills until I get my period? If I do that should I use back up protection?