Pill and sex

Okay so I've been on the pill for a month but I missed about 3-4 days and I take it at different times each day 😁😁 and so my boyfriend and I never use a condom, but last weekend he cum inside me, he liked it and now we always wanna do it, it's good at the time, but I always get scared after that I'm pregnant, how can we break this bad habit, I'm only 16 but he's 18 😁😁😁