please hellp

Im gonna haave sex for the first time. In 2 weeks. I just started bc. We will use condoms. Im scaredof pregnancy. If i use plan b the next day to calm my fears is that okay? My bf and i are ling distance so i wont see him until january. I am going to get an iud by then and will never need plan b again. What do you think? I feel its the best for me for this time only. I know people disagree but it would give me piece of mind