Brown discharge

I had unprotected sex last week &I was ovulating. I recently got sick this weekend &one of the symptoms was vomiting &I kept thinking it was a symptom for pregnancy cause I couldn't hold anything down &when I laid on my stomach I always threw up. Anyway, yesterday &today I had brown discharge but it wasn't a lot, it was more like 1 time a day thing &im not worried but my period isn't due till next week so what can the brown discharge mean?