hello, i had sex on may 9, and got my period that following day. it was a normal period, fairly heavy flow. i also took a plan b within the 72 hour window. then on june 5, i got my mext period, right on time. it was a very heavy flow and lasted until the 9th. so now today is the 13th, and i had some light spotting in my underwear and when i wipe, what could this mean? is there a chance i could still be pregnant?