Fertile window?

So I’m new to TTC (only my second month) and so I started taking OPKs this month out of curiosity knowing that it is likely to say not fertile until later on in my cycle... but on CD8 I got a flashing smiley face on the clear blue digital test which apparently shows high fertility but not peak/ovulation day. I’ve tested every day since (it’s now CD11) and I still have that flashing face. It may be important to note that CD 5-7 I tested and got a low result so I don’t think the testing thing is broken... Glow predicted my fertile window to start tomorrow.

Basically I’m confused. Does the fertile window happen that early? Is the test thing broken? I’m going to go with the dip tests next month (if I don’t end up pregnant obviously) since they seem more reliable.

Any advice on this would be appreciated!