I am 46, no children, never pregnant. I am going through (peri)menopause now. I started my period at 11 years 7 months.
Officially - Menopause is the moment when it has been 1 year since you had a period, Peri-menopause is the time of the changes leading up to that moment, but most people just use menopause for both.
I started at 37 with minor changes to my cycle, some heavier, going from 30 days every time to 29/31 alternating cycles.
At 42-43 I started skipping periods, 1 missed, normal for 8 months, 2 skipped normal for 6 months, etc. I now appear to be on the bi-annual plan; 2 periods per year.
So far, the herbal supplement “Estroven” is working very nicely for the hot flashes. Those range from a “slight glow” to the fear that spontaneous human combustion will take place.
When the changes started, I had to seriously think about what I was going to do about children. I realized that I really have no place for a child in my life and was able to make the decision not to have one and be OK.
I have read that it is not starting young that makes early menopause (but that is one factor), but never being pregnant or having children is a more significant factor contributing to the earlier start of menopause. The most significant factor is genetics.
Ask your mother and paternal grandmother (you have the most of their genes) to see what their age was when they started perimenopause and when they were actually “post-menopause”.
Ask your maternal grandmother and aunts too. Find out what their experiences were. That can give you a better estimate for your timeline.
Remember, just skipping a period doesn’t mean the end. You can be in perimenopause for as long as 10 years before you have your “menopause moment” when you haven’t had a period for one year. Your fertility will delcine but it is still possible to get pregnant
At 34-35 there could be other things happening, so a good checkup with your ob/gyn is in order.
Good luck.