I recently went through EMT training. I had to do two shifts with an ambulance service. What I already knew but had reinforced was this: if you are not actually in the process of dying, don’t call the ambulance. You probably won’t get to the hospital any quicker (at least where I live) and you will get a bill for around $600 to $700. In my very limited experience, the ambulance may very well be tied up taking someone to the hospital who “doesn’t feel good”.
But if you do have a problem, they will see you in the ER right away if you come in an ambulance, while it may be 3-4 hours if you are driven in. (Besides, we live in a rural area, and pay an annual subscription. Haven’t used it yet, by God’s grace....)
When I left a hospital after a short stay I wanted to ride home in my daughter’s car (I was fully well enough to do so) but the hospital insisted that I use an ambulance. Got a bill for $400 for medical transport I didn’t want or need.