15ish is when periods stop. I think 10ish = infertile.

if I were you I'd just add a supplementary tbs of evoo (I'm biased probably the type of oil doesn't matter to my diet (maybe every few days til you feel cramps? more if it doesn't happen after a couple months?) then when I feel my insides puff up (not from fat but from building up n preparing to shed tissue. given it hasnt happened to you in months, there's no way you won't notice??) I'd add a long "belly dance" portion to my workout until I bleed that month. if the sensation passes without blood, I'd add more oil n resume my normal work out (which includes targetting those muscles cuz this trick is fire)

before marketing, what's now called belly dance was a workout people who menstruate do together to ease cramps and assist in removing things from your insides. if they did it to music that's just because dancing is also a necessary part of the human diet that modern people don't recognize. anyway, idk how to describe it better than making your uterus dance. it sounds like you workout enough to know what to flex despite my poor explanation, but if someone reading this doesn't have enough there to be able to flex those inner muscles or has no clue what I'm talking about: start with leg raises. put your hands under your lower back to make it even easier. feel it in the same area you feel menstrual cramps and also more in the center of your body too? nvm this isn't better.

if someone could explain the science version of what I said, I promise it would help.