Conception date confusion.

Brandie • Mom of 2 girls💕 1 angel in heaven😇 preggers after trying for over 2 years 🧚🏻‍♀️ Expecting twin boys in October/November💙💙

So my cycles are usually around 24 days.

I found out I’m pregnant on the 27th of Feb.

my phone has dated the pregnancy at 4 weeks and a few days. However I would have been on my period around that time.

I had sex maybe around the 6th of Feb( 2 days after the end of my period and the 14th.

Which day did I most likely conceive? Thanks for any guidance.