Have you talked to your parents about this at all? Don't dismiss the idea out of hand. At least turn thinking they won't support you to knowing they won't. Or they may surprise you.
We spend a good third of our lives working. It's great to love it. But a lot of work is dull and blah. You will probably have to go through at least some of that in order to get to the good stuff.
So talk to your folks about wanting to make a change. But this is not you just holding out your hand for more money. Rather, offer a partnership. Can they help you change course and go to school part time? And you would work at a paying job part time. You would open an account and save as much of your salary as possible. And your intentions are to pay them back for their tuition expenditures, in full, for both a new degree and your earlier studies. Make the deadline 10 or 15 years from now.
This way, you cut any argument about money off at the knees. You show determination and responsibility.
Work a job during this time for money and no other reason. You're not climbing the corporate ladder. You're just there to earn money. Your love or lack of love for this job is immaterial. It's just a cash register to you.
Go to school for both psychology and photography/art. I say art because there are a ton of photographers these days. A background in art will make your photos better.
I am also suggesting spreading out your academic pursuits because you don't want to get stuck in a rut again if you turn out to dislike both of these interests.
Also, keep taking pictures, and start to submit to contests, either local or online. Build that portfolio.
You're going to be busy. And you probably won't have a lot of money for dating. Your girlfriend sounds lovely and understanding. I hope she stays that way.