I had sex March 31,2016 - April 3,2016 I ovulate durning this time. My boyfriend came in me a lot within those days so about 14 days later (April 14,2016) I started spotting pink and brown than got light red but wasnt enough to feel up a pad or a tampon this was going on for about 4 days . My cycle is due April 18,2016 and it didn't come and I'm regular. Is this implanting bleeding or a period?