Hello Primrose, I'm sorry to hear you're suffering with VA, it really is awful because it's 'there' all the time. Apart from the advice re potential prolapse, all I can add is that treatment will take time and estrodiol or an equivalent internally, with an initial loading dose daily for 2 weeks, plus cream daily externally is really the only way. The applicator for the pessaries is thinner than the one for the cream and if you use lubricant, it is possible to get them inside without pain, even if you are on fire. Your symptoms being so bad, you do need to get a plenty of treatment inside too. Even then, you may find after 2 weeks, your symptoms are not under control enough and you need daily treatment permanently. Many of us on here do.
I use coconut oil as a moisturiser after each time I pee or bathe too. Also it may be you'll benefit from testosterone as that can really help the urethra from being so irritated if estradiol isn't enough.
So it's good you've got treatment quickly but it may get tricky to get a high dose long term. If you look on the private lives section here at a thread called 'the burning club' there's plenty of advice and experiences. That said, even at a higher maintenance dose, you can have flare ups. I don't want to alarm you but just want you to know it's very treatable but it's helpful to read as much as you can on the subject in case your GP is limited in knowledge.
I believe there is a move to get the information leaflet updated inside the packs of pessaries and cream to say that it's a safe treatment daily long term.
Wishing you all the best, but definitely have a good read on here.