I wasted my soul, how can I get a new one?
You have two options: just deal with it and do another run, or cheat.
If you want to just cheat it back, first open developer console (press F12), and run data.mysouls.value = 1
. Also, if you get arrested for cheating, you can just run data.jailtimer = 1
and get out of jail in a second.