I mean first of all, doctor is not something you can just do because you want to do it. It depends on what your grades are and how smart you are. Also being a doctor is a very responsible job and I dont think its just about money.
If physics and maths is the thing you enjoy why not go for it, i know money is important and it is but slowly find out what you like and what makes you happy. Why do things you dont want to do and be unhappy when you can do the things you want to do and become happy