Can't help about diabetes, but if I were you I'd definitely ask for a haemochromatosis test. Not many doctors are aware of it, and it's surprising how many people have hemochromatosis, especially if you are of Irish decent (also known as the 'Irish Curse'). The treatment is easy, you just have to give blood weekly, monthly, 6 monthly or yearly, to bring the iron in your blood down, if you don't have any health issues, your blood will go into the national blood bank to help those in need. Haemochromatosis (hemochromatosis in the US) is not dangerous per se, but in later life the high level of iron build up in your blood could clog your liver, heart, etc. You need to research it. See
https://www.haemochromatosis.org.uk/