I have a feeling

Okay I’ll get right to it! I had sex on the 4th unprotected. So the withdrawal method was the one we used. We always use that method now my period is due on the 11th so 5 more days. But the next day on the 5th ! My body felt sooo idk how to explain it. It was like my body way of saying I’m changing. Now I get period symptoms before it comes on and these where not the same at all. Is it possible to maybe just know your body telling you. “Girl you’re period” without peeing on a stick yet or missing a period yet? I know my classmates said she knew the next day after sex it was just a feeling. But maybe that was just her. Do anyone have any stories or advice?