I was due for my depo shot on sept. 3rd 2010. But I had my period aug. 16-24 2010 and was spotting sept 3rd -5th 2010 and now I have been spotting for over week now. Could I be pregnant?

Having a period followed by spotting is not a sign of pregnancy.

I suggest taking a test to be sure, but its likely that your hormones are a bit off balance due to the birth control