feels like my millionth post

Hello all. POAS addict here, first cycle TTC baby number 3 and I swear to god I remember nothing. I have questions about opks. I got a nearly (like this is almost positive and the next one def will be) positive opk yesterday morning at 8 am. Got one equally dark but not darker at noon. Got one ever so slightly less darker at 9 pm. I took one this morning at 6:15 (not fmu) the same darkness as the night before. Today at 3 pm I got one that was very light and the same right now (6:30). I’m on CD 15 and typically ovulate on 16 or 17. Since my LH levels are going down should I assume that my LH surge occurred and that it was just weak (and what does that mean for TTC) or should I continue testing since I never got a try positive? Either way we will continue to BD tonight. Just looking for insight I suppose. Thanks for hanging in till the end! (Included is a pic of the darkest I got on LH strip Yesterday)