OPK - can you have high E3G but never ovulate?

Mari • Hi! I`m a designer, blogger, mom, and shiny object addict.
I'm using the Clearblue Advance which measures E3G (estrogen) surge first for high fertility, then LH for peak fertility. I've had high fertility (blinking smiley face) for 4 days now - can't figure out why it's not shifting to peak fertility?!  (solid smiley face)
​LOL, our interest in doing the BD is wearing out!!