Answers for this/anyone experience this too

Chelsea Alexis❤👑🌹 • Wife 💍 Mother of 1 👪 and baby #2 on the way 🤰🤱
So, a childhood friend of mine has been staying at my house for the last 2 weeks. I was supposed to get my period in another 9 days as of yesterday. She got her period the day before yesterday and then mine came yesterday. Not to mention I started having a period every other month since june and got one on time the last two months 😒 so confused lol