Let me give you a small perspective. I am a graduate from a private medical school in Khi, worked there and now in specialized training.
First and foremost, decide if you want to be good at something or be average. Being average is easy you can do it in any field be it medicine, economics, finance, engineering. If you want to be good/great you want to do something that you LIKE, REALLY LIKE.
Please realize that you will wake up for the next 40 years atleast and most likely do the same thing.
People quit during medical school, internship and residency. So please be very VERY careful. Do something you like and you will be very successful in it and make money too, be it photography (fashion photographers, wildlife photographers) economics, car restoration, entrepreneur.
If there is anything particular that you want to know about medicine let me know and I might be able to give you an insight.