Your parents are in the wrong. They sound horrible. they should never have spanked you, and in the UK that would be seen as abuse. They could have been charged with assault.

You forgot to wash the dog, not a big crime any way as you say it is unfair to wash a dog too much.
Get away from home as soon as you can, in the mean time don't argue with them there is no point, be compliant and plot your escape!
My parents were horrible too.