Endo or not please help

I do have a question and I’m hoping someone may have had a similar experience.

My hormones have felt completely out of balance for years, and I’ve had quite a lot of PMS symptoms. I also had two premature babies with no clear cause ever found. Before getting the Mirena, I had very heavy periods, period pain and cramping. Some months were quite painful, while others were manageable, but I’ve also had ongoing lower back pain that doesn’t really go away.

I’ve had the Mirena for about three years. The first two years were actually really good, but over the last year I’ve started getting pelvic pain, bloating, constipation and other symptoms again. I also notice depressive/low-mood symptoms before my period, along with what seem like histamine-type symptoms around that time.

Could this mean the Mirena isn’t controlling my symptoms as well anymore? And is it possible that I could have had endometriosis all along without realising it, even though my period pain was never severe every single month?

I’d really appreciate hearing from anyone who has experienced something similar.