Janine I am so sorry that things haven't got any better for you and that you are having to wait for your shunt revision.
You must be so frustrated and angry at the moment and who could blame you nuhuh but I would try your hospitals PALS and tell them what is going on and how long you're having to wait for this revision, and they should be able to help things along for you by liasing with the Neurosurgeon who you are under and your Neurologist.
I know there are bed shortages and waiting lists but the fact that you're struggling to function on a daily basis and in so much pain can't go unchecked or untreated. Here's the link PALS
where you can find your nearest office and you can then give them a ring. I've used them myself for similar problems and they are very helpful and quick. This is why I always advise our UK members to use them when they come across a problem with seeing their Neurologist and/or Neurosurgeon.
Let us know how you get on and hopefully PALS will get things moving for you.