1) you can always go back to the corporate world
2) you can work EMS part time, and go back to the corporate world
3) OT is all too common, and can help make up the difference
4) full time is only 3 or 4 days a week, so you can pick up a second job.
I worked IT from 2003 to 2005, than EMS full time from 2005 to 2015ish, and now I'm back in IT, working full time in InfoSec, making more than I ever made in EMS with better hours, and I play on the BRT a few times a month. Don't get me wrong, I might love what I do, but love doesn't pay the bills.
I will also caution you, that it is tough to take a 50% pay cut without a change in lifestyle, or a sugar momma/daddy who is giving you extra $$$. it will be an adjustment, esp going from bankers hours to days, nights and weekends. But it's definitely doable, and life is too short to be in a career where you are unhappy.