Do you know the medical system in USA?
There is no such thing as MBBS over there. Students who want to become a doctor, first have to go through 3 years of a pre-med course. It’s equivalent to BSc. in India. After that, they have 5 years of Medical school. And then residency i.e. Post graduation.
My point is, it is normal there for people to enter medical school at the age of 20-21.
The profession of medicine is indeed long. It will take up most years of your youth.
But trust me when I say, this is the only profession, with 100% job satisfaction. If you are completely dedicated, that is.
So, to answer your question, no. It’s never too late.