Cramps?

My period is irregular and I got my period the 6th till the 10th of November. I'm pretty sure I ovulated on the 24th. My boyfriends stuck his penis in me once and I don't think I'm pregnant. On two apps my period says it will start in the 4th or the 7th of December. Iv been having cramps. Is this normal. Do you get cramps a week before your period