Hi Jobo
If you are definitely post-menopausal by 4-5 years then your hormones should not be fluctuating to such as extent that they give you these symptoms - oestrogen levels fall dramatically to a low level approx 2 years after last period although there is still some hormonal activity after this - but not anything like in peri-menopause!!
At your age 75 mcg is definitely not too high either and yes patches should give you a fairly stable dose of oestrogen.
By the way you do still produce oestrogen after menopause - it is an essential hormone after all - it is just produced elsewhere in the body.
The other thing is if you had premature menopause - or premature ovarian failure - then sometimes the cycle can resume spontaneously, although you should be getting signs of that if this is the case.
Re the utrogestan - you were using it on a conti basis and as Dancinggirl says it does not necessarily control bleeding so well on higher doses of oestrogen at the recommended dose which is 100 mg orally. Better control is achieved through vaginal use but of course you would not want to do this on a conti basis. I am wondering why you had such bleeding on cyclical utrogestan? Were you using 100 or 200 mg? It could have been that the lining had built up ( can't look at other page to see what you said!) and it would eventually settle. The dose should be 200 mg and you could always take for a couple of days longer for a few cycles to try to control the bleeding - was this suggested?
The side effects sound like they could be due to the systemic effects of the Mirena as others have said. This is why I wouldn't have one even though they are very efficient at delivering progestogen to the womb - because all my HRT has been bio-identical from the start (more or less!).
I wouldn't have thought you need to change from the patch if this is suiting you and you have felt well on this dose in the past?
Just a few thoughts
Do you also use vaginal oestrogen to keep things healthy there?
Hurdity x