hey it's not your fault, you're just answering their questions, nothing wrong with that :)
I get it though, it's hard for me to give any kind of simple explanation, especially because people have a million follow up questions. But they're only asking bc they're curious! You're not obligated to answer everybody's questions if you don't want to, but you're certainly not hurting anybody if you do!
My strategy is usually to give short/vague answers whenever people ask me questions (about most things, but especially about my health), and it lets me avoid long awkward conversations, but it inadvertently turns me into the "mysterious" guy. I don't mind it, but sometimes I wish they knew I don't mean to be rude or secretive, I just don't like telling my life story twelve times a day 乁( •_• )ㄏ