This is so confusing!

Holly K • TTC #2 since miscarriage January 2016
So my hubs and I have been TTC for #2 for 16 months now. Tried Clomid and now trying Femara. Started taking opks on CD 10 and got what I think was a positive test on CD 13 (lines were faint, but equally faint). Now I am having my usual ovulation pains and ewcm..opks have all been negative since day 14. How is that even possible?!?!