Far as I'm aware, you don't need the oestrogen to offset the progesterone, because I've had the mirena peri and post meno with oestrogen (hrt) only for 9 months out of something like 5 years.
It's difficult to disentangle all the symptoms. I felt better with the mirena because it stopped catastrophic bleeding. There is a bit where it (the coil) goes silent, because it's doing its job, at which point I stopped thinking of it as a foreign body having an unknown effect (I could see the effect, no more bleeding, I didn't hugely care about anything else).
I became significantly worse on oestrogen, but again, difficult to disentangle symptoms because there was so much other stuff going on in my life (crazy stressful job, youngest had just left home, etc). I felt as if I was on a roller coaster that I couldn't get off ...
But yes, your symptoms were bubbling before the coil, I remember. Has it got the bleeding under control? How is the bladder?