Operate or not?

Hello community!
I wanted to get some opinions from people that have experience with Endo!
I am 30 years old and I've always had excruciatingly painful periods with vomiting and nearly passing out, getting dizzy and needing to lay down to not collapse. I always had pains on the left side, quite far left. Early on already doctors checked but said there is no cysts so basically figure it out yourself. Then i went on the pill and at first it was better but slowly with the years symptoms slowly started resurfacing, never as intense of course. I went off the pill for about 2 years in my mid twenties and got the pains back full force. However, I was told what is weird for me is that the pain starts with the day of my period and lasts up to three days, but not a lot of heavy pain throughout the month, usually. Also, I don't have heavy bleeding, never did. I could last with 2-3 pads a day on heavy days. I was told that's not very typical for Endo. Then I got the IUD Kayleena and I had issues with it. Pain did get significantly less intense, but MUCH more frequent. I started having minor pains up to ten days before my period and 7 days after, so basically whenever. Usually taking pain meds was enough, but sometimes it stayed lingering in the back no matter what painmed i took, not intense, but still painful...still very annoying. It also increased again with time. I am not sure if it is my natural period or if it is due to my body not liking an object in there. Sometimes it is the left side pain i am used to, sometimes it's central, which i never used to have before i got the iud. Actually when I got the IUD i remember being confused about the location of the pain, as my period never actually hurt there before - so basically where the uterus is. It was always much more to the left for me.
Well in any case, with getting older and Endo gaining more recognition I went to a few different doctors specialized in this field and all of them said I am likely to have Endo, and I also have signs of it in my muscles surrounding, so this Adenomyose or whatever it's called.
However, up until now I didn't do the operation, because I was scared...of it being Endo, and also it not being Endo and me still not knowing then what's going on.
I have an appointment now for the Operation in March, and my operating doctor recommended replacing the Kayleena with the stronger version - Mirena.
I am scared though, of all of it. I don't really love the idea of getting stronger hormones and a bigger "foreign object" implanted in my uterus, but if I really have it I won't have much choice I guess.
I guess I am still not sure if I reeally wanna go through with the operation. It scares me. Things possibly going wrong - it's still surgery - all of it.
Imagine getting surgery and then finding out it's nothing...I mean apparently my doctors assume they'll find something, but I'm still worried.
I am wondering if I shouldn't try other things first, like maybe changing diet to get rid of the stomach pains and bloating I also frequently have, or i don't know. Alternativ methods.
I'd appreciate some opinions of people that have experience with this...