SOS Condom broke- didn’t realize I was in fertile window

Boyfriend and I were having sex with a condom and the condom busted. I am not on birth control. Took a plan b immediately after. After looking at the app on eve, it said that the day we had sex was a 33% chance of pregnancy. I’m so stressed because this was during my fertile window (2nd to last day of it ending). How accurate are the fertile windows on the app?? Thank you in advance.