hi, ok i had my period on august 7-9, my period only lasts like a few days and it was at the time i expected it. I had unprotected sex on august 21 and im not on birth control and i didnt take the morning after pill.. my cycles are usually 30 days exact so i was expecting my period on september 7 or 8 but instead i got what seemed like a period on august 28 which was one week after i had intercourse so im not sure if this is my period coming early or if it is implantation bleeding? it started out brown and pink but gradually got more red and it lasted 4 days.. so does it sound like its implantation or just an irregular period??