Your fem is a very beautiful girl !
I can't say with any certainty what has happened in your case.
What I know is this question comes up often
I also know many fems will attain a very large
pre ovulation swelling, very swelled
I think very often many people mistake the pre ovulation swelling
for the actual ovulation.
This creates confusion and discrepancy in due dates.
Just be certain to mark down that shed date and do a count forward for a possible due date.
This might help should your fem go longer then
your original calculations put her at
(You said she had ov date 12-03 , puts Due Date early April about the 12th)
That's the best I can do, I'm certain someone with far more
experience then me could have more answers for you , ha ha 
Good luck with your season
. . . Lar M
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Boas By Klevitz

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