help pregnant or not

I have been on bc for 3 years. this past month i skipped my period on it and didn’t take the sugar pills. my period was supposed to come this past week so i stopped my active pills. it never came but had sex during my period week and then had cervical mucus discharge after sex, never happened before. had sex on the last day of my period which was friday and started my new pack on saturday. i have not missed any pills and why do i have the cervical mucus it is clear and sticky. concerned i could be pregnant because i didn’t think on bc you got cervical mucus. should i take plan b i am concerned