TTC Using Glow!

Ive been TTC since October 2013 using Glow and nothing yet.  I find that Glow tells me I'm most fertile different days from other apps and online calculators. Does anyone else have this problem? I also testing using a BBT and that's so up and down I don't know what's what! I have also been using ovulation test strips but the DR told me those aren't 100 % accurate? TTC is so hard :(. Getting discouraged.