So I got decapitated in Immortal Mode (TIM console command) and only realised MANY saves later as I had my helm equipped at the same time. Anyway, commands like showracemenu don't work but I've managed to fix my character using this:
sixchange
sixchange
player.removeitem 000DB5D0 1
sixchange
sixchange
IanHead who suggested the "removeitem" part. Basically, the first two commands re-add your head but with a decapitation scar. IanHead suggested the scar was an equippable item. So the third command removes it. Then the last two reverts your character back to normal

Just thought I would let others know because this seems to be the only solution.