Some questions pop up in my mind. For example: will you actually enjoy theoretical physics?? Many high school students read pop sci books and dream of becoming a theoretical physicist. They don't realize that physics research is nothing like it is in those books. It is not at all just thinking about worm holes and time travel. Rather, it is very hard work. You have to like a lot of pain and discomfort to enjoy this kind of work. It is certainly not for everybody.
I'm not saying this to discourage you. But I'm trying to give you a somewhat more realistic view of research. How will you know you will like physics?? The answer is easy: get some math and physics books and start self-studying. If you enjoy books like Kleppner, then you will probably enjoy a physics education. Enjoying it means not only liking the theory, but also the intellectual struggle of finding solutions. It might be a bit extreme, but in my undergrad I occasionally spend nights awake in my bed because I couldn't sleep without finding the solution to some (very silly) problem. It is that desire to find a solution that is the characteristic of a scientist. If you don't really care about solving problems, then research is not for you.
Another point is whether you are good enough for physics. You have to face reality: a lot of people attempt to become physicists, but only a few make it into grad schools, let alone professorships. Sometimes the students find out that physics is not for them. In other occasions, they are just not good enough. You should absolutely realize that you might not be as successful in physics as you would like. Having a plan B is always a good idea. This might consist of taking some engineering classes (or double majoring in engineering), or programming, or something else.