Chemical/miscarry or just early period?

I never get my period early but yesterday It came. A WEEK early. I had tender breasts and cramps 2 days before the start. Also a lot of stress going on right now. How do I know if I’ve miscarried or if my body just decided to menstruate? A 23 day cycle this time when my usual is 35-40, exactly 2 weeks after ovulation. Thanks a lot if you can help!