Hi, I had my period on the 28th of June 2017 and it ended on the 1st of July 2017. My periods come irregularly. On July 3, I had unprotected sex around 6 PM and on July 4th, I took a Plan B pill at around 3 PM. It is now the night of July 8, and I have found a light amount of watery red blood in my cervical mucus. Can someone please tell me what this might mean and if I should buy a pregnancy test? Help! Thank you in advance!