Should I be this paranoid ?

So basically I’m 17 , and have been dating my boyfriend for two years. Obviously my raging hormones drive me to wanna have sex. But doing it makes me so paranoid after because of how young I still am and getting pregnant this young is one of my biggest fears. I watch my ovulation calendar , use a condom , and withdrawal. What are the chances of me still getting pregnant ? I don’t know I just need to learn ways on how to let myself just calm down and not worry about it so much. Don’t worry till you’ve got something to worry about right ?