Pregnant?

I really need help understanding ovulation and stuff. So I got my period November 6th and ended on November 10th. I had unprotected sex on November 15th(only two stokes then stopped). No condom or bc. My app tells me my fertile window in the 17th till the 22nd. Period should start dec 4! I'm NOT trying to get pregnant. What I'm confused about is can I get pregnant if my body hasn't ovulated? I was feeling pains the last couple of days. What are my chances of getting pregnant from his Precum if there was any? Can I only get pregnant during ovulation and not my fertile window I don't really understand. What do you think?