What day looks positive?!

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Started testing on CD16 because I have a 34-36 day cycle. I was getting nervous that I had somehow missed it but then I got a pretty dark line on CD19. I thought I’d definitely have 2 dark lines today on CD20, but it wasn’t at all. Was CD19 my LH surge? We DTD on days CD17-19, and will again tonight. How many days after CD19 should we try? Thanks!