Career question.

I'm 44 and have been nurturing my increasing interest in medicine and the human body for several years now. I find so much fascinating about our physiology and I see the intellectual challenge of making a diagnosis exciting. I have no formal background in biology and have a BS in architecture from 20 years ago.

If I could go back I would pursue medical school, perhaps finding my way to rheumatology eventually after years in emergency medicine. But I feel it's too late at my age to change careers now especially given the amount of schooling I'd require. It feels like I'd be in my 50s and starting at the bottom, not to mention the financial restraints.

Are there careers that don't end in a MD that could still get me close to the action so to speak? I know that being a doctor makes you the boss but I'd like to be as close to a peer as I could be instead of being in a supplemental position. Are there other roles that get close to the diagnostic parts of medicine that aren't based on patient advocacy? How grueling do you imagine it would be to go back to intro classes in your mid 40s? A career change to medicine at this point feels more like a pipe dream - am I right?