CD 16 and + OPK?

Today is CD 16 and the opk was positive, so fast and so dark!  I had a positive (I thought I did) on CD 8 then again on CD10.  Not sure how many days past ovulation I am, but I thought I was around 5 days.  Now I get a positive opk (negative the last 4 days), I am so confused, and sad.  If I do only ovulate tomorrow, then no chance this month for me to get pregnant, unless my husband has super sperm :) lol.  But I also googled it quickly, and some women had a positive opk about 6 days past ovulation, it then got a BFP.  Apparently the OPK can be used as an early pregnancy test, but dont want to get my hopes up.  I am guessing that I am POAS wrong or something, maybe wrong time of the day.  I also checked my cervix, and it think that it is closed and very high.  I guess it's time to do more research and make me go crazier :)