Negative opk 8/28, 7 dpo!!

Tete
Okay so I took a clear blue digital 8/21 and a wal mart brand and both were positive that day. I actually felt ovulation taking place within a few hours throughout the day. I also had EWCM. Anyways, today I went to the bathroom and had a slightly thicker EWCM .Does anyone know what this could be?