My last period was from 08/13/12- 08/19/12. According to my "my days app" my next period should be somewhere around 09/18/2012. I have been spotting since 09/03/12. Not heavy enough to wear a pad or tampon. Just a pantie liner. But still spotting. What does this mean? I also had unprotected sex on 08/23/12. Could this play a part?

So you are using that uterly worthless app?

Unless you do a basal temp reading every AM and keep a chart you really don't know when you actually ovulate because you can ovulate anytime of the month, every or even MOST women don't ovulate on that assumed schedule, though some will, and as a result that app is worthless unless you are proven to actually ovulate during that ASSUMED period programed into it.

I agree, all these apps are waste of time, but anyway.

Of course you could be pregnant, wait another week and do a pregnancy test first thing in the morning