I got a physics / econ double degree, and I recommend against studying econ in college, unless there are some really good professors at the college you go to. What you suspect about philosophy is true, and even more true for econ. I learned ~2 things in the econ classes I took that I hadn't learned in my personal reading on the subject (whereas I learned quite a bit of physics in classes), and so feel like those classes were wasted opportunities. I strongly recommend a field like computer science instead, if you have the least bit of aptitude for programming. If not, psychology seems like it could be super useful, but the cognitive science is few and far between, or electrical engineering fits with physics pretty well.
(I do recommend reading Adam Smith's On The Wealth of Nations at some point if you haven't already. It's easy enough to get through, and it's a remarkably good foundation for the field.)
((Also, *brohoof* :3))