brown discharge

I have been taking the pill everyday at the same time for atleast past 2 months. After my birth control ended I skipped the placebo pills and started my new pack. Two weeks ago I had unprotected sex but the guy did not cum. About a week later i started having light brown discharge. And my period isn’t supposed to start for another week. Could this be because I started my pack immediately after or should I be concerned about pregnancy? thanks