I Had Unprotected Sex On The 29th A Few Days

I had unprotected sex on the 29th a few days ago, and took Postinor 2 the day after. However, my boyfriend did not ejaculate in me (withdrawal method, pulling out). Took him about 5-7 seconds after he was out to ejaculate nowhere near my vagina. I decided to take Postinor 2 because he was not sure whether or not pre-ejaculation fluids got in. How big is the possibility of getting pregnant, and when am I going to find out if I'm pregnant or not? Thank you