Hi all!  My hubby and I just started TTC. This is the very first OPK I have ever taken. Clear blue gave me an empty circle so I know I haven't had my LH surge but I do see a faint blue line.  Will it continue to darken each day?  Should I start testing twice a day?  Glow says my fertile days will be from 1/5-1/11. My last menstrual cycle started on December 16 (so I guess that means I'm CD 17?). Here's a picture of the test I took. Any help would be appreciated!  Happy New Year to all!