Need a little advice!

So my boyfriend and I have been having unprotected sex for the past few weeks and he cums in me everytime. I am on birth control but during our first week I was on an antibiotic that I was told would weaken my birth control. So... like an idiot.. i stopped taking it and continue to have unprotected sex and he cums everytime..My period is suppose to be next week but I wake up a little nauseous everyday and have a few other signs. Should I wait it out to see if I miss my period or be worried now?