first time sex

Yesterday around 5:30-7:30pm I had sex for the first time. I took his virginity and he took mine. The only thing I'm worried about is that he took the condom out and came immediately in the condom and I'm worried he might came in the condom at the moment he as inside me, and as he did so, he immediately took it out. That's what I'm worried about. I get my period in 8 days so I'm worried, what if he wasn't quick enough and I'm pregnant? Is thay possible? I've been clocking the days on Glow and yesterday was a Blue day and it said 3% of Pregancy. Does that actually make a difference?