How much longer should I wait 😱😱

My husband and I have been pretty safe using condoms. I just made an appt last Friday so I can get on birth control to ditch the condoms. My husband and I decided to have one last hurrah before he leaves with the boys on a road trip (I am within my 90 days at work so I couldn't go) we forgot the condom and he came in me. I've downloaded so many apps and went 3 months back on all my periods and every one of them says I was fertile that day. But the egg part varies either on the day or a few days after. He thinks nothing will happen because apparently he thinks it don't take just one time 😣