Bfn again, am i still too early!

Another bfn this morning, I am using first response as I've seen they are the best, AF still not due until the 14th. What am I missing? Did I actually ovulate when I think I did? Glow says my AF is due on the 18th but I know I'm due on the 14th I get it on the 14th every month. So I'm 5 days until due date. Do I need to tweak my test again. Why can't it be as easy as 123 for all of us TTC!