I've been on ortho tri cyclen lo for about 6 months now, and take my pills everyday and on time. My periods are always off and almost always have at least 2 periods per pack. I'm on my 3rd placebo pill and still nothing ? My fiance and I only have sex maybe once a week (with 2 kids it's all I can do lol)... Please tell me someone else has had this same situation and didn't end up pregnant

*update* I now have one placebo pill and have yet to start my period. I have two children and so far haven't experienced any pregnancy symptoms other than major breast tenderness ~ which is also a symptom of pms.
Ugh...It's so hard to tell what's normal on this pill seeing as since i've been on it my period has never been regular or on time. Any advice would be great thanks.