Pregnancy or Implantation bleed?

Dear Ask The Doctor: My husband and i had sex on the 6th of this month(3 days ago). My period come on the 9th of every month like clockwork and today it is not here... is it possible im pregnant? the only symptoms of my cycle i have are sore breasts and that could really be a symptom of either right? am i pregnant?? :)

Dear Megan: It is difficult for me to say whether you are pregnant or not based on your symptom alone. Your bleeding could have been due to your periods or an implantation bleed. You would need to do a pregnancy test to find out. I wish you well, take care.