Mine was a pathological diagnosis. I had no clue until I had a hysterectomy and they found it when they biopsies my entire uterus.

I was bleeding (like clots gross!) and cramping all the time, not just during my period. I had a good GYN and he did an ablation procedure on my uterus (I was done having kids). He said if that didn’t work in stopping the symptoms (which it didn’t) - it was adenomyosis. And this was confirmed when the uterus was removed.

I read online that a normal period is only 2-4 tablespoons for the whole week, and realized I'm bleeding way too much, so I went in and got a sonogram and they said my uterus is 12 weeks gestational size.

on accident during surgery to diagnose endometriosis lol

i was 12 and had actually only started my period 6 months prior to diagnosis. I has basically been bleeding heavily (one over night pad and super tampon in 15 minutes) for 6 weeks straight when admitted into hospital. i had only been stopping for now longer than a week before bleeding again for a few weeks. after about 3 months being in and out of hospital, multiple mri/mra’s and several ultrasounds the doctors found it. they were shocked i was 12 and seemingly developed the condition for no reason. said i’m probably the youngest ever to be diagnosed. also had blood testing done and discovered that my endless bleeding cycle was partially due to a familial blood disorder that can’t be treated. oh well, but we’ve sorted out most kinks now nearly a decade later. i forget it’s a condition i even have sometimes