I'm On Zoloft 150mg Once Daily, Ativan 1mg 3 Times

I'm on Zoloft 150mg once daily, ativan 1mg 3 times daily, and a low dose birth control pill. Lately I have been waking up extremely nauseated. I have had unprotected sex several times in the past few months where my partner ejaculated inside me. I am a twenty year old female and I am unsure if the medications are causing it or if I could be pregnant.