A.M.
Could be!!! When I had IB with my first pregnancy, it was 10 days past ovulation which was the day before AF was due. It was bleeding for 1/2 the day actually, so I figured I just started a day earlier than expected. Then spotting for 4 or 5 more days. I tested that day, before the bleeding started and it was negative (I looked and looked for that faint line! lol).
It is soooo hard to wait, but not much else to do. :-)