OPK help

[MadamRose]

I’m 15dpo and 5 days late. I’ve been told by a doctor my AF might not come and I might just ovulate again.

I took this and it’s not positive but it’s stronger that I often get on day 12 (I usually get a positive on day 13). I’ll put some explains in comments so each test is obvious
This one is today’s OPK around 11am

 

[MadamRose]

Two cycles ago clear see it was lower at 12DPO than today’s. I’m so confused.