It's my first month trying to track ovulation and I haven't had a positive OPK. The highest it got was 0.78 on the morning of CD15. I tested twice a day (more on CD15) My cycles are usually regular between 27 and 29 days. I had EWCM on CD14 and 15 and some cramps on CD15 which was predicted ovulation day. Could I have ovulated despite no positive OPK?