At last
a clued up GP
as stated, at an early age you need to protect your heart and bones. HRT can help with this. As can regular weight bearing exercise, a good diet, 'me' time and as much fresh fruit and veg. as possible. There is a search button here so any queries you can press that 2 C if there are other similar threads. Ask away.
Your GP may well send you for a scan of your womb to check the lining 'depth' before beginning treatment. Let us know how you get on.