Uncut😗 , also how fast do you need to take a plan b for it to be affective

So my boyfriend is uncut down there and Sunday was the first night we had sex...well kinda I made him stop cause I got scared cause you know what unprotected sex can lead too... since he is uncut he doesn’t feel comfortable in a condom and he says he can’t cum if it’s there cause he doesn’t feel any sensation cause of the skin and he says if he feels like he’s even close to cumming then he’ll pull out but it’s all the “what’s it’s” for me, i don’t wanna get on birth control cause my sister works with my doctor. I know I can just take a plan b but idk fast you need to take it after have sex or any of that, plz give me you opinion.