opks can be very confusing and dont work for some people. i have read that you get EWCM 24-48 hours from o. you should DTD when you see EWCM though cause the little spermies can live in it until O day. the most fertlile time is 2days before and day of O for best chance of conception. i dont know if you will get another good reading from your opks though. my first cycle i got some positives and didnt concieve second cylce no positives and did concieve. good luck! :-)