@Reallybadidea I haven't had my vitamin D checked in about 4 or 5 years. I'm so glad you reaped the benefits of it, hopefully I will see the same sort of improvement.
@Mischance The doc today mentioned 6 monthly injections (see below update). I'm sorry to hear about your fractures though, I hope you are well now.
Well, update: I had a good chat with the doctor who was very reassuring. I guess she could see I was feeling a little upset and repeated several times that "it's really not bad" and that I shouldn't be so worried.
She is sending me for a blood test to check calcium and Vitamin D levels and has started me on Calcichew straightaway. Once the bloods are back we will have another chat and determine which of 2 options I want to go for - a drug (bi-something - some PPs mentioned this earlier) which I would take once a week or an injection every 6 months. She said she would likely be recommending the drug given that I am young (her words not mine!!), otherwise in good health and not on any medications. I will do some research before deciding.
I asked if the treatment is just to slow the progress of the disease and she said "not at all", that the aim is to improve things and then repeat the DEXA in a year or so.
I asked about exercise and if there is anything I should avoid and she said absolutely not, that exercise is very beneficial. I intend to up my walking and review my other exercises as I see from reading this morning that anything that involves bending at the waist or twisting at the waist, is to be avoided.
I did wonder (aloud) if a consultation with a physiotherapist would be a good idea and she laughed and said she had just been about to suggest this so I am going to do this also, just for advice on movement and exercise.
All in all, while still a bit upset, I am feeling much better about things. I told my mum who was a little upset but only because she could hear in my voice that I was but she is fantastically practical, told me it has never stopped her doing anything in her life, that she never gives it a second thought and reminded me that she didn't even have a diagnosis until late 60s so it's good that I have caught this now and can hopefully prevent it from getting worse.
Thanks to all of you for responding to my (slightly panicked) post, I am honestly very appreciative!