So I have been taking cerazette contraceptive pill for 10 days. I didn't start whilst on my period, I started taking them to avoid having my period, but this happened anyway. I've not changed my pill back to what it was which is a combined pill called rigevidon. When will I be covered for sex? I'm confused whether to wait 7 days, two weeks or the whole packet 3 weeks. Do I count the week and a bit from the old packet?