This is an interesting question! You’re not alone in this experience. Having to pee when you lie down at night actually has a name: nocturnia. It can happen for a handful of reasons that may or may not be related to endo. One has to do with circulation and fluid that builds up in the body. Nocturnia is common in people with diabetes or a higher body mass index. (It might happen with endo, but it hasn’t been studied as far as I know.)
With that said….
I don’t have either of those conditions and nocturnia happens to me. I do have severe interstitial cystitis, which is just bladder inflammation. It’s not related to endo lesions, per se, but IC is very common in people with endo. And my bladder sensitivity/urgency symptoms are worse around ovulation and during my period. I sometimes have to pee right when I lay down to go to bed.
Excision surgery did help ease some of my bladder sensitivity issues, maybe because he got rid of some of the extra inflammation in my body. I also saw a urogynecologist after my excision surgery. That’s someone who specializes in urinary issues in female bodies. He suggested I see a pelvic floor/spinal physical therapist specifically for these bladder issues. And she really helped! https://endometriosis.net/living/bladder-pelvic-pain
I definitely would suggest talking to a urogynecologist or endometriosis specialist who knows about endo and bladder issues. My first OB/GYNs and urologists told me my endo wasn’t related to my pee problems. And they were wrong! Let me know if you have any other questions, and I’ll try to point you in the right direction - Keri (endometriosis.net team member)