Really freaking out!! 😞

I'm on CD16. This is my first actual cycle after my miscarriage one d&c on August 25, 2015. AF was Sept 28-30 with some midday spotting on Oct 1. I've been taking the First Response ovulation tests everyday since I stopped my period and there have been no surge... Not even a test line is showing up! When I got pregnant with my lost pregnancy, I ovulated CD16. And being today is CD16 I was expecting to see something on my OPKs. NOTHING!! Am I not ovulating?? Or are cycles longer after miscarriage? I'm also charting my bbt and they are still low like my pre-O temps the month I got pregnant. Ugh! Starting to really freak out!