My cycles are very regular and usually between 29-31 days long.  I have been tracking my ovulation for four months and it's typically between CD 11 and CD 14.  This month I started tracking early just to see where I was.  To my surprise, my Clear Blue OPK & my other cheaper brand tested positive on CD 7. (Just two days past my period). I'm a little confused on how it's so early this month.  Any chance this is a false positive or would I possibly be ovulating twice this month?