OPK newbie

Okay so I've never charted with opk's before. I started on CD11 because I usually O around CD14 (or so I thought), today is CD 13 which is the bottom test, but all I've been seeing is faint lines on these. Shouldn't they be more noticeable? Like not dark but at least more visible. 
I took two test on CD 12 because I thought I had taken the first one too early in the morning, but I'm wondering if these cheapies even work all that great. So is it normal for it to be super faint until o day or is this weird? 

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