Hi, this may seem a bit of a weird question

Patient: Hi, this may seem a bit of a weird question. It is not exactly for my health, but rather for general knowledge. I am a 20 year old woman, and I have recently realized that the back of my head is flat, also known as brachycephaly. I am confused as why I have a flat head. As based on my research online, brachycephaly seems relatively easy to treat in babies, and my mother tried repositioning tirelessly. One thing that has come into mind is the hardness of my head. Could my skull be harder than others’ skulls? For prenatal nutrition, my mother drank one cup of milk per day for the first three months, 4 cups for months 4-7, and 6 cups during the 9th month during pregnancy. However, based on my research online, the information indicates that expecting mothers should have 3 servings of calcium daily regardless of the stage of pregnancy. Did I receive calcium overnutrition, making my head harder to shape?