Thanks for your query at DoctorSpring.com
I understand your concern.
Well, having sex just 3 days before your period rarely results in a pregnancy, because you are not at all likely to be ovulating then, my opinion would be that you could not have conceived then.
Secondly, taking it outside the 3 day window would reduce its efficacy, but not totally, it is not possible to say in percentages how much the efficacy would be reduced.
Then again the withdrawal method was used.
All said and done, it is not possible for you to have gotten pregnant 12 days back.
On the mini pill, you often have a period that is lighter than average, also cramps often occur.
If you wish to be very sure, please take a repeat test after a week.
All the best
Please feel free to discuss further.
Patient replied :
So the pregnancy test I took 8 or 9 days afterwards was probably not late enough to tell?
Yes, atleast a fortnight has to elapse, to have a reliable test.