So I did my first opk cycle- stupidly excited at seeing two ones on a stick of any kind! Negative OPKs from CD8-13 then I ran out and didn't test CD14 then bought some more and got a positive around 11:15am CD15 (yesterday) then negative again that same afternoon! So I'm thinking a short surge or it began the previous day when I didn't test perhaps. Ewcm the last three days including heaps this afternoon so looks like my instinct of ovulating around cd16 was pretty spot on. I'm so proud of myself- lol I'm so easily chuffed!