How possible is it that i could be pregnant if i had unprotected sex 2 days before ovulation according to my "my days" app?

Very possible: Sperm can live in the woman's reproductive tract for 48-72 hours. Therefore, unprotected sex within 3 days of ovulation may result in pregnancy. If your period does not come when expected you need to take a pregnancy test. If you are within 5 days of unprotected sex you may consider post coital contraception such as ella (ulipristal acetate).