Newbie Questions

Ally
Hello! 
I am new here and am TTC. Honestly thought it would be so easy but ughh it isn't :( Have only been trying for about 4 months. Couple of questions. 
1. I have tracked my BBT for the last 2 months and it is up and down every day. No patters / visable spike. I wake up and take temp before getting out of bed every morning. Am I doing something wrong?
2. I have been using a First Response Digital ovulation test every day and it is negative and on day 14 now (cycle is only 26-27 days). Have never had a positive. Has anyone else used this test? 
Feeling sad. Is there something wrong with me?