So here's the deal in as uncomplicated as I can put it my period is extremely unpredictatable.

date of my last period : 7/28/12

I did not have a period in august, I took pregnancy test and it was negative two different times.

my expected period for september was supposed to be about 9/28/12, and according to my Ovulation calander I'm supposed to be fertile on 9/24/12, I had intercourse on that date, and haven't had a period. I also took an emergency contraceptive on 9/28/12, then I took a pregnancy test on monday 10/1/12 which was negative and today 10/3/12 I started to have some blood, which I thought might have been my period but it is extremely light, so I was thinking that maybe it was implantation bleeding...haha geez idk...lol. I can't be pregnant now...lol would be nice to have a little feedback. Initially I would like to say of course I'm not pregnant because I took the emergency contraceptive and also had the negative home pregnancy test, but just got a little freaked out when I saw the blood and then read about some women having implantation bleeding. Can any one offer any insite or some advice? It is much appreciated...thank you for your time.