First month using lo loestrin fe

I started lo loestrin fe December 4 when my period started. My period according to eve was supposed to start yesterday but it's normally off by a day or so. I am about to take the last brown pill today at 10 before I start my new pack and was wondering if that was normal and that maybe it was supposed to start when I got done with the last brown pill. On the 29th me and a guy friend were playing around and he had touched himself and I believe he wiped his hands as some Precum would have been on his penis from me giving him a bj and this has happened before where I was scared and I got my period so I feel like I'm fine. But should I miss my period or not? Is that normal the first month