I was on Estradot 50 mcg for most of the time I've been on HRT. I increased slightly to 62.5 mcg when I started teststerone as I didn't want to become T dominant. I felt absolutely fine on this dose (50 mcg) - as Dotty says. It is only if you are taking HRT for a premature or early menopause to help prevent osteoporosis when the actual levels could be important but in practice the dose at which symptom relief is obtained will give you the minimum leves required anyway, from what I've read. I agree with her - if you felt fine on 50 mcg then stay with it especially at your age.
You lining should continue to shed if you have the balance between oestrogen and progesterone right. Normally if you have no other problems ( thickened lining, firboirds, polyps) the lining should gradually get thinner with each successive cycle provided the progesterone is sufficient for the oestrogen dose you are taking. I would suggest you mention the very heavy bleeding to your doctor in case they want to have a check over since it is so long since your last period, and perhaps they might refer you for a scan or investigation just to check all is OK?
Dotty that's really encouraging to hear about feeling fine on taking Utrogestan all the time!

Hurdity x