No LH surge?

Second month TTC, 29 years old and the first month that I've used the opk's. I'm on cd 15 with no positive test, not even a faint line. Started testing on cd 8. No increase in CM?? Did I miss it? Am I not ovulating? Testing once a day in the morning. Was worried that I may have some issues getting prego to begin with and this is not helping.