Positive? Or not??

I have decided to use OPK's this cycle. It's the first time I have ever used it so not sure exactly what i'm looking at. The directions say that the test line needs to be as dark or darker than the control line to be a positive.
My test line was so close in colour to my control line that I am not sure if it is the same or slightly lighter. If it is really, really only slightly lighter should I record it as a positive?
I am trying to BD as close to O as I possibly can as we are trying to gender sway for a boy. Going on past cycles FF has given me two possible O dates....just to make it even harder....arrggghhhh. :wall:
I had to discard this mornings temp as I woke up with the flu and my temp was really high, and FF marked O as 4 days ago :doh: