So I had sex on June 18th, my highest fertile day, but I took a plan b right after. 2 weeks later I got my period but it was super light an only lasted 4 days and there were no blood clots. (I usually bleed for 7 days) and the month after my period came again but it was extremely short (3 days). It was more like spotting than a actual period. I also keep getting nauseous and dizzy. Could I be pregnant?