My friend is telling me I can still get pregnant. I don’t believe her

I had sex yesterday with ejaculation inside me

My period is due in 3 days.

Has anyone conceived from having sex a few days before expected period?

My friend is saying that I can still get pregnant while having unprotected sex right before period.

I say it’s impossible because you have to be ovulating to get pregnant.

I tried googling it and can’t find much of any info besides less than 3% chance.