Temp shift v opk help!

Jan • Mummy to my 😇Angel Findley born sleeping at 39 weeks 💙.. And 😇 angel Robyn late miscarriage at 16 weeks. 🌈 Lewis 02/09/2020 👼 👼👼ruptured ectopic and two miscarriage

Hi all help!

So I normally temp and opk, normally I get my temp shift the day if my

Positive opk, I have a super short surge.

However this month positive opk cd 13 (3days earlier than normal) but not temp shift till cd 15, opk negative .. did I ovulate cd 13 or cd15??