Question about ovulating and PCOS

I’ve been diagnosed with pcos, but still have somewhat normal periods. I had an ultrasound this past Monday and had a follicle measuring 16.9, which I guess is pretty good. I’ve had some mid cycle spotting the past couple nights but haven’t had a positive ovulation test. Is this normal? Does the spotting indicated that I’ve ovulated, or should I go by my opks? This is my last natural cycle before starting Femara. Any insight is greatly appreciated.