Hi (((pnativetexan)))
How soon HRT is started post op varies from doctor to doctor. Many do start their patients on it right away when both ovaries have been removed.
As far as the issue of vaginal dryness, here is what Vivelle says on their website:
If you use Vivelle-Dot only to treat dryness, itching and burning in and around your vagina, talk with your healthcare professional about whether a different treatment or medicine without estrogens might be better for you.
www.Vivelledot.com
Of course, in your case, there could be a number of symptoms that arise.
I would encourage you to talk further with your doctor about starting HRT or waiting. There is also of course a wealth of information on the web regarding this issue. Perhaps you will be able to decide for yourself after some research.
As far as the walking, listen to your body. It sounds like it is already sending you some good messages.
I hope that others on HRT who have had a BSO will be along to share their experiences with you. All the best!