HELP!

Hey girls! So... me and my boyfriend have a very active sexual life, a few weeks ago, I stood a few days at his apartment. My last period started in May 24 and ended in May 30, and we had sex the week after that, without using any kind of protection. My period is late by four days and I'm starting to worry, I'm only 18. What do you girls think? I'm taking a pharmacy test tomorrow morning. I'm sorry if there's any grammatical error, I'm Brazilian 😁