Help!?!?

So, I had sex with an ex on June 12th while I was on my period. My period stopped the day after. And then I had sex with a different ex on the 23rd, which according to this app I was at 22% chance of getting pregnant.

The ex on the 12th did not pull out since I was on my period because we did not think he would need to, but on the 23rd that ex did.

So if I do turn out to be pregnant is it likely that the baby would have been conceived on the 12th or the 23rd? This is a very delicate situation because the two exes hate one another. So I'm stressing out, badly.

And please, no bashing.