TMI!!! Implantation bleeding or period TMI!!

Martha • I am 31 years old. Hubby and I are TTC #1.Gah! I Didn't think it would take this long!
Okay so I need some advice been TTC for almost 2 years. DH and I had sex 12 days ago period is due in about 4 days. Is this implantation or AF coming ? Never had this before. Would greatly appreciate your advice! Thanks