Just an update, I saw my GP and she recommended trying AIs as its easier to start and see if there are side effects rather than not have meds and change my mind later. My oncologist has put me on Letrozole as my bone density was good for my age. So 9 days taking them so far and the only increase in problems that I feel is hot and cold flashes, at night is the worst, and then an increase in pain in my joints generally. As I'm already on good pain relief, it bearable. My oncologist said that if there are any problems we can swap medication or stop them altogether as he thinks the risk of my type of cancer coming back is quite low because it was caught so early. So I feel very lucky that that's the case. All I'm concerned about now is the long term effects of bone thinning, but my GP says they will keep an eye on that.