No changes to CM yet?

Natalie
Hi ladies! I'm tracking my cycle for the first time this month by checking my cervical position, CM, using OPKs and taking my bbt
I haven't noticed any change at all in my CM and I'm on day three (CD 15) of my fertile week. 
I'm still figuring out my cervical position and if there's been changes. I also am only getting very very faint lines or no lines at all on my OPKs. Currently testing at 7am and 7pm. 
I'm worried this isn't the norm. Can anyone shed some light on what I'm finding?