In the early 80's I was given the opportunity to shoot weddings and portraits professionally. I already had a caeer in insurance (not the most exciting but it was regular income and paid the bills). So, I started doing weddings as a part-time income stream with a view to going full time once I was happy that doing so would be financially okay.
After 6 months or so, I was truly tired of working to ther people's requirements. The fun had gone and I dropped it like a hot stone.
That's only my story but the point I'm making is that it might be worth doing photgraphy as a sideline for a while. Everything is possible and you might love it and make loads of cash into the bargain. here's hoping. However, having a "Plan B" is a good tactic and takes the pressure off to some extent.