Painful period, endometriosis, or something else?

I’m 27 years old and have had a period since I was 13. It seems like over the past few years, the first day of my cycle has become more severe to the point I dread it.

If I don’t take Advil the night before, there’s a good chance I will spend 3 or 4 hours of my day basically debilitated, often with hot or cold flashes and on several occasions throwing up. Yesterday involved shivering terribly with two sweaters on and under two blankets, and eventually also throwing up. I end up spending as much time as I can it a hot shower or bath and sitting in bed leaning over a pillow, listening to music to distract me. I’ve also recently had cramping in the area of my stomach below my belly button which is much worse than when it’s “deeper” or more towards the ovaries.

My period typically only lasts 5 days but the last 3 are pretty light (mostly brown and not the fresh blood). I feel pretty normal and don’t experience cramping those days, besides maybe faintly on day 2. I would say I have a pretty normal flow the first days as well.

My dad’s mother and sisters all have had endometriosis. They described the typical very heavy flow symptom, though. My mother has never had any issues like this.

I am not on any bc and don’t wish to be (I have never been on or wanted to be on it, but am planning to try to have a child anyway). Do I just have a bad day 1, or does this sound like something more concerning?