Hi Jess, and welcome to the forum.
Your story is very typical of IIH. It is not a pleasant illness to have to deal with. It sounds as though you have a responsive medical team, and that is very helpful.
I have a lp shunt, not a vp. Mine was very quick and easy, all has gone well. It seems they do things a bit differently in the UK, For one thing, if they had you lay flat on your back for one hour after having a lp, your chances of getting a low pressure headache is much smaller!
Perhaps one of the others who have had a vp shunt will be along to give you some assistance.