feeling down on CD17

This month I used two different opk kits and thought I got a positive on CD 11 or CD13. My temp took a nose dive CD13 so I assumed ovulation and was SO excited. My temp spiked back up to where it was and looked like it was slowly rising but after only 3 days it dipped again. All my tests are negative. And I'm really scared I'm not ovulating this cycle. 😔😔😔 feeling really down about it today.