well idk man!? help a girl out!

So today is supposed to be my most fertile right.. well shiiiiiiiiii my line is gone again! After I thought it would continue to get darker BAM it almost doesn't exist! 
So my question is, could I possibly be on my way to getting pregnant. Since it's possible( but not as likely) to get preggo anytime of the month maybe I'm on my way? Idk but I've been using preseed and doing my opk's but they are whacked this time when normally spot on? 
I guess my best bet is to continue to ttc and hope for the best? Any ideas? Here are my tests... dec 7 should be my most fertile!