Well its great you have gone to the doctors and they have ruled out an UTI and, I presume, a prolapse. Perhaps you could drink during the day….make a goal of some kind and then decrease the fluids in early evening. Most of us don't drink enough water anyway. Melatonin never worked for me…..magnesium glycinate is calming but start with only 1 per day…I switched that one from night to morning.
I don't think anything can overcome a racing mind and what we really need is sleep. May I suggest advil pm maybe…lots of older people I know rely on that for better sleep. I don't use it because it is ototoxic. You sound like me…bladder doesn't wake me up…I just wake up, and, like you get up.
Let me know how you do on your journey to restful sleep and if you find something that work's for you.
I think the Melatonin works for a few hours maybe…then it wears off and yeah, my mind is hard to calm down. I can't take Advil; I take Xarelto (A-fib) and the only OTC pain killer I can take is Tylenol.
Sweet dreams to you, as well.