I had a 2 day positive OPK, then a negative day (tested 2x that day) then the day following the negative I had ewcm...then the following day a temperature shift. SSo, Im assuming I Oed the day I had ewcm, since the shift happened the next day. But, the O day I had a neg OPK. From my chart, it looks like I had a decrease in LH before Oing? Is that possible?