Opk and cm is off

Jade
Alright so I was wondering if anyone had any suggestions...my CM is a clear snot-like consistancy around day 10 of my cycle but my opk does t usually register high Lh until about day 16 of my cycle. That seems to be really far off from eachother from what I'm reading. 
Any ideas? Which should I base around? 
Thank you in advance.