Me and my boyfriend have been together for 3months and are going through the honeymoon stage still so we are having sex all the time, I was due on my period on the 30th September and I didn't come on until the 6th October, I am normally always on time. Before my period due date we had sex on 27th. I was on for 5/6days as normal and come off my period the 11th. Since coming off my period I have had sex 4times. I am now experiencing bleeding on the 17th October exactly a week after my period, it's very pink/red and very light and slight cramping? What is it? What should I do?