Re - feeling of fullness - I agree with Taz. Check with GP. The constipation (if unusual) would certainly give a feeling of uncomfortable fullness. However if it is unaccustomed - and there is no reason for it eg change of diet/fluid intake/exercise/meds etc then any persistent change in bowel habit should be checked out.
Re Orthogynest pessaries being given irregularly - is this what you meant CLKD? If so it can be given indefinitely on repeat prescription. I had a quick look back the thread and I see silverlady already mentioned that estriol is very different from Estradiol ( that is used in Vagifem).
From what I've read (see ref below) it allows plumping up of vaginal/bladder tissues though the Beta oestrogen receptors, but binds to the alpha oestrogen recptors by a factor of 7 x less than estradiol. It is the alpha receptors that are dominant in uterus and glandular breast tissue.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3003469/There have been studies that show no increase in serum oestriol levels after the intial priming phase (ie on an atophied vagina) and no thickening of endometrium etc so there should be no worries about using it even with past history of breast cancer. I can imagine there may be mild side effects initially but once the plumping is done if you keep it going for twice a week there should be no absorption.
I think silverlady said back in the thread that estriol is not converted to oestradiol - but the other way round, therefore you won't make the stronger estradiol from any oestriol that is absorbed in your body.
Any form of HRT including topical/vaginal oestrogen carries the same warnings and quote the WHI or the Million Women Study conclusions about risk - that's standard. It scared the life out of me way back when I started them and had read nothing about HRT and at the time didn't want to go on it!
I hope this is helpful and not confusing ie I hope I've explained clearly and not too much of a ramble.
Hurdity x