Positive Clearblue OPK but negative Wondfo?

Kristin
I have been getting the flashing smiley on my Clearblue advanced opk for the last few days and finally got the solid smiley this morning. However, my Wondfo is still negative. I just tested a Wondfo again...still negative. To be safe, I BD'd today and will again tomorrow...but has anyone had any experience with this before?  I'm CD 25 after Femara 2.5 mg CD 3-7.