What is happening to my body..?

Today I am 4 days late for my period, me and my SO have unprotected sex often. I took a pregnancy test the day after my period was due (October 19th) and it was negative. I have white discharge like crazy, and I just started to get a light burning sensation down there randomly. When I wipe I get this (pictured below) Does this look like implantation bleeding or my period? Should I test again or wait?