|Errin is a ortho micronor generic, right? It is a pop- which means it has only progesterone. It doesn't have a placebo week or anything like that. So each pill has the same amount of hormones. Each pill in your whole pack, you get a steady level of hormones the whole time. No placebo week, no sugar pills, nothing.
It isn't less effective. The only thing about pop's that makes them less effective is if you don't take them right- you HAVE to take them every day at the exact same time (or within 3 hours) or it is considered a missed pill and you might get pregnant. You don't get a one-pill freebie or a 6 hour window like you do with combined pills. However, if you take them correctly, they are just as effective as any other pill.
POP's don't control your period. At all. The only reason they say you are supposed to get your period during the last row of pills is because you should've started the pills during your period.. .so logically, a month later, you should have it again. But that doesn't happen with all women.
Is there a reason you are on Errin and not a combined hormone pill? Usually you only take POP's if you have to for some reason.
Yes, you most certainly threw off your cycle by taking plan B! That's exactly what it's supposed to do.
Once you have taken 2 days of pills, you are completely protected (at the same effectiveness levels as any other pill). That is, as long as you are taking them at the same time every day, and not throwing up or anything like that.
I hope that helped clear things up for you, it's too bad your doc didn't explain this stuff!!!