While ttc cm checking

Ok ladies so for all of you who cm check and have gotten pretty good at it I have a question. Now I know I could probably Google this but i know every one is different and I'd like multiple opinions.

Ok so I've learned alot about cm I'm not an often checker but when y'all ovulate how long does your ewcm last approximately? Here's why I ask..

I dont often check because i dont seem to really get alot of cm even when I ovulate I just dont notice a change but I know I do ovulate because I get my periods regularly well now (as of midnight, now 1:15 am) I'm 7 days late but ever since my first day late I've had heavy ewcm and have had it for the past 7 days

I dont think I'm ovulating now especially since it's not really normal for me to get heavy cm even when I do ovulate so I dont see why it would change now? But anyway I have tested the morning of 6 days late and it was a bfn

So any thoughts on the extra long cm and of course my main question

How long does your heavy stretchy cm last? Or is that a pregnancy symptom And my test is just to early for a bfp?

So sorry this is a bit lengthy I added spaces so it didn't all run together lol