this is confusing so bare with me ...

okay i’m gonna try and explain this the best I can lol ... so me and my bf use pull out with my birth control pill ... I have been sexually active since july with no scares .. now does this mean every month i’m okay since I take my pill perfectly? or as each month passes do my chances of pregnancy differ? like if I don’t get pregnant on the pill one month (taken perfectly) could there be a different result the next month and so fourth? or am I basically in the clear since I do take it perfectly and we’ve been okay everytime? sorry this is confusing i’m not sure how to word what im thinking