Oh wow. My first period was nothing like that. I remember waking up one morning and seeing the stains in my panties when I went to pee. I nearly fell off the toilet. I was a late bloomer, according to my pediatrition and even my endocrinologist (I was diagnosed with Growth Hormone Deficiency when I was 12, so I saw an endocrinologist regularly), and was sort of thinking I'd never get it, but I got it when I was 14, a week before starting my freshman year of high school.

I was beyond relieved to finally get my period, and before I even started high school. I felt normal for the first time in a long time. All three years in middle school, other girls kept exclaiming about their first periods, and I couldn't wait to have mine, feeling that something was abnormal about me because I hadn't had mine yet. I even started looking up medical conditions to see if I had anything that would prevent me from having periods. Lol.

So yeah, I felt mine was past due.

I remember going to my mom and saying "I think I had my first period, but I'm not sure." When I explained what I saw in the bathroom, she said something along the lines of "Okay, we'll go and get some pads.".

So yeah, maybe it's something your mother had done to her, and her mother had done to her. A tradition of sorts. I do hope she didn't hit you to terribly hard though. Leaving a mark on your face isn't slightly in the least.