It can be when you first start and your period could be abnormal for you entire period life its nothing to worry about I am 15 and have had it for 1 yr and it is still abnormal so yours could become normal or stay abnormal.
Menstruation
It is 12.
Menarche is the first menstrual flow onset of puberty in girls while menopause is the time when ovaries of a woman stop releasing eggs.
The average age for menarche for girls is under 13 years of age. However, individually speaking that can vary depending on several factors including weight.
Breast development and menarche aren't directly connected. Both of these things are part of puberty and everyone develops differently so some girls may see breast buds before menarche and some won't see them until after menarche.
The average age of menarche (first period) for girls in America is around 12.5 years old, although this can vary depending on genetic, environmental, and nutritional factors.
menarche; 12
Ovulation does occur before menarche. Menarche is the term used to describe a girls first period, menstruation will only occur if the woman ovulates. With that said some people will experience vaginal bleeding as a result of hormonal imbalance which will look like menstruation but without ovulation occurring beforehand, and sometimes we call that menarche - because we've no way of knowing if ovulation had occurred.
age 15
The average age of menarche is around 13 years old. Anything between 10-16 years old is considered within normal range, but girls can reach menarche far earlier or far later.
Menarche is the term used to describe a woman's first period.
It is not abnormal for period blood to have a smell/odor.