I’m so sorry to hear that.
So it depends on how severe your endometriosis is on whether or not it can only be diagnosed by a laparoscopy or if an MRI is possible (but severity of the stage of the disease doesn’t correlate with the severity of your symptoms - some can have mild endometriosis but have debilitating pain whilst someone else can have it advance but have minor pain). Less advanced endometriosis can only be diagnosed through a laparoscopy because you can’t really see it on a scan. More advanced endometriosis which is deep infiltrating can be seen on a MRI. And even then, you need a radiographer (or whatever they’re called!) experienced in endometriosis to be able to identify it. I’ve obviously read a lot about it since I was diagnosed!
I very randomly had a couple of extremely painful periods which was highly unusual for me so I saw a gynaecologist. He did an ultrasound that showed a large endometrioma on my ovary (it’s a cyst filled with old blood and something that can be seen on an ultrasound). It’s the side where my ovulation pain was always quite noticeable and at this point, my youngest 12 months old so it would have been there during all my pregnancy scans.
An endometrioma is a sign of more advanced disease so he sent me for a MRI which showed my ovaries were stuck to my uterus and my uterus was stuck to my bowel with some adhesions on my bladder and other parts of my bowel too. After I had my first, it was always very slightly uncomfortable to pee, but so so slight I never thought twice of it. The ultrasound I had with the gynaecologist who found the cyst didn’t see any of that, because it wouldn’t come up on an ultrasound but it was advanced enough to show on a MRI.
So it’s taken me by complete surprise that I have so severe endometriosis when I was pretty much symptom free (apart from ovulation pain!) and was able to conceive twice. From what I’ve seen online, my experience with endometriosis is not unusual.
Not saying you have it, but I wouldn’t rule it out because they didn’t see it on an ultrasound as it wouldn’t show on an ultrasound. Women’s health is an area that doesn’t get enough focus and too often doctors dismiss women’s pain as normal when really it isn’t!
(Just to add that I had a few MRIs over the years to look at my liver for another reason and that too didn’t show anything, because the MRI was looking at my liver and not at my uterus and surrounding areas, so a MRI for your back pain may not have been looking at the right place and as I said, a MRI is only useful when the disease is at an advanced stage).