I have experienced this. You’d think my FIAT on steroids would provide a nice flat plane on which to lay, but it didn’t, at least not until I used the plank across the tire. But, before that I tried in vein to sleep in the back, the back seats, the front seats, and never once did I sleep well. It was impossible. So, I can imagine your experience. Worse, you had to live in your car. I just spent one night.