13 days of my period

Su

I got the Depo around September 28, then my period started after I took Plan B, (I took the plan be 2 days after I got the shot), it coincided with my actual period, which was due a week after I got the shot. I have had my period for 13 days. I have had sex several times during my period. Would having sex affect the length of my period? Sorry for the long story.