I unexpectedly got a pretty dark line on a cheapy Opk at 6:45pm last night and I decided to back it up with a Clearblue dual smiley test before bed at 10:30pm - which came back with a circle meaning 'low fertility'..... However when I ejected the stick both lines were pretty dark. This morning I got what I would consider a positive cheapy Opk.... so I'm confused how the CB could have said low (not even a fertile flashing smiley?!) a few hours ago... Would love your thoughts on this.... I only have a couple of CB tests so was hoping to save them for when I was pretty sure I'd get smileys!!