Period

So I'm on both control. Normally, I start bleeding the morning after I take my first day of period pills, I take my pill at 7am. This is my second day, and I've already taken my pill for the day and I'm not bleeding yet. My boyfriend goes to school in Detroit, so he left at the beginning of January, and I had my period for that month. Obviously because he's been gone, we haven't had sex so, why am I not bleeding yet? I'm kinda panicking