Creamy cm but opk neg?!?!

Renae • 💙 '09....💙 '11....💔 '14.... 💔 '14....💔 '15....💔 '16....💔 '17....💜 12/12/17
Ive just noticed that I have what looks like creamy/yellowy cm yet the opk test I took last night was neg! I'm pretty confused as it says that I get the creamy/yellowy cm after u ovulate! Should I retake a opk test now even though I took it at 6pm last night?????