Student of neuroscience. I've been drifting for months if not years. Thought about going to medical school after (GEM) but that's looking very unlikely at the moment.
Even if you have half a chance at medical school you really should go for it. Doing medicine instead of mechanical engineering at Uni was probably the best decision I made by accident at your age.
Its not a job though, it pretty much takes over life. I've worked nearly every Xmas or Newyears for the past decade, at the age of 35 both me and my wife was at the library writing up our respective PhD thesis on a sunny Sunday morning because we didn't have time mid week due to the day job.
I've had days at work when it makes an episode of ER/casualty look calm, including literally having my finger on someones beating heart!!
COVID wasn't in anyones plans, but I've been humbled by how so many people have pulled together. Seeing people walk out of hospital when you have seen them at death door is a rewarding feeling few people get to experience but am lucky enough to see nearly every day.
However telling a young family their mother is never going to be with again after an unsuccessful 1hr+ resuscitation effort is an experience I'll never forget, the fact literally 10 seconds after leaving the relatives room I was called to deal with another urgent situation helped at the time to distract but on reflection wasn't a great way to process any emotions.
For me medicine is the only job I have ever done or ever will do, but it really isn't just a job its pretty much part of life.