So I don't have any pics (yet) but just a general OPK question. I believe I got a positive OPK about CD 14-15, but got lighter starting CD 16, and def much lighter this morning, CD 17. So going from a positive to a negative OPK mean that you've already OV? This is my first month using OPK, so I don't yet understand how the hormone works, like do you only have the hormone before you OV, or before & until you OV? DH & I DTD CDs 11-15, JIC, but not sure if we should continue since my last positive OPK was CD 15, and I've read that you can OV anywhere from 12-36 hrs after....Thanks for any advice!!