I have had this happen to me too, if you have ALOT of emails in your inbox (like me...800 +) then just scroll down (boring) and look for a new email. What you have simply gotten is an email that was past-dated, and most likely spam. It will be in there, and most likely way back in the beginning of your emails. It has happened to me before, and i've always found the little buggers. Hope that helps!