Unless your love for coding (in addition to a strong desire to work in the field) overrides your desire to continue working in finance and law, I would keep it a hobby and continue to grow it on the side to gain the experience. Perhaps you can continue developing your coding skill set on the side and start adding apps to the App store as a side-gig in that case.
If you're entirely serious about getting into coding and trying to fast-track, perhaps take some online courses. Keep leveling up on your coding skills for sure. I know finance + IT/dev is a huge market with lots of opportunities. I would envision the same thing for law + IT/dev as well. Perhaps freelancing or volunteering on coding projects in your spare time would be a good way to gain even more experience. In the meantime, I would definitely pick-up more languages to learn if it's something that truly interests you. Get yourself involved with Github and Sourceforge. The more stuff you do on the "side" for coding, the better it is for you IMHO.
Sounds like there are a ton of opportunities ahead of you, and you're smart enough to figure something out that will let you have at it while reaping the rewards. Perhaps, ultimately, you could start a business or consultancy that combines all three aspects into one somehow. Or at least, you'd be able to offer legal services, financial services, or IT/Dev services independently of each other if nothing else.