I slept in my car because I couldn't tell my parents I had the dates wrong... and wasted their money.
Why didn't you just tell them the truth?
I'm not sure, I did know it was a bit shitty to do that to them.
Mistakes happen and it is okay to let people know that you made a mistake. It would at least prevent you from having to sleep in a car.
I did it all on purpose to prove that I had my own place to live and that I wasn't living with them.
I think that it is normal for people to make mistakes. You should just tell your parents the truth next time and then you will be fine.