So scared!

I’ve had the Mirena IUD for a little over a month now, and about two and a half weeks ago, I had unprotected sex (yes. I know it was stupid.) my period is a few days late, and I’m freaking out! I’ve always had an irregular period, but I’ve had a pregnancy scare once before. Any *nonjudgemental* advice? I’m 19 years old and I can’t drive. I don’t have a trusted adult to get me a pregnancy test.

EDIT/UPDATE: if you give a helpful comment, thank you so much! I’d rather not reply. Trying to remain anonymous