Femara help

Has anyone taken femara and not o'd? This is my 4th round but first at 5mg. I'm on CD 25 now and no bbt shift. I've been doing temping this whole month and opk's for about 10 days now. I got my first pos OPK 2 days ago and glow says that I should have ovulated yesterday but then this am... No temp shift. What is going on?!? Anyone have this problem before?