I recently had 4 days of +OPK's? I was testing at about 8 in the morning and then 5 in the afternoon and was constantly getting lines of the same colour or darker then the control line? This hasn't happened any other month and I was wondering if anyone had heard of this? I even thought i might have had a 'dud' batch but the line has eventually disappeared?

I have no idea when O would have been? Would it have been calculated from the first +OPK? Any thoughts muchly appreciated!!