OP
Cut head! Get over it!
I don't think you have any idea how little money you would be awarded!!
Money in these cases is awarded for financial expenses incurred both at the time and in the future, such as for somebody needing a paid career as a result of an injury. A SMALL amount is also awarded for loss of use or a body part, eg. If you lose a finger I think the going rate is UP TO £5k....
So what are you expecting to be compensated for!? A small scar at worst?! Even IF a judge ruled the restaurant were negligent, I think you would be awarded.... £10?
But actually, I think the most likely result is that the judge would rule that you were negligent parents and that having a cut head is just one of those things. (Based on what you've said I'd agree with him, too.)
Rally OP, someone under 18 in my family (recently) sustained mild brain damage and had organ failure and their parent left their job to look after them, yet they did not need to pay for a carer, work kindly made the parent redundant and long term brain and organ damage were sub-clinical / too hard to prove, therefore they were told by a legal team that they would only be awarded £4K to cover travel expenses to the hospital and nothing else.
I think you need a better perspective on this issue!