help with due date!

Hannah

Hey ladies! so I came off the pill in October. my last period was from October 23-26. I got a positive (more like 6 positives 😆) hpt on CD 66. how in the world do I gol about calculating my due date?! I know I'm not 8 or 9 weeks pregnant because I tested once a week basically from the time I stopped the pills to when I got my bfp. I ovulated. on Dec 12 or 16 according to my temps. anyone have any guesses on how to do this? Do I measure from where I should have got my period in November? thanks!