I thought of nearly everything on a recent admission, except headphones - had to send my siblings out to buy some for me! I took my laptop and a massive pile of DVDs. There wasn't wifi but just having well known sitcoms like Friends, and upbeat films I know by heart, on in the background was comforting. I wouldn't have been able to concentrate on or enjoy new ones but old favourites were great.
Oh, bulldog clips!! The ward I was on had new disposable curtains with old fashioned rails that were pretty incompatible, so there was a gap at least a foot wide when they were supposed to be drawn around. So no real privacy during intimate exams etc. Bulldog clips would have been good to keep them together for these occasions, and while getting changed etc.
Lip balm and handcream!!
And actually, Febreeze to squirt inside slippers. They did get a bit stinky.
More sleepwear and undies than you'd think you'd need, unless you have someone visiting daily who can bring these in as and when you want them.
Antiperspirant.
My hospital's water wasn't too bad but other patients had bottles of squash, so something to consider.
MP3 player with audiobooks? You may not always feel up to reading and as with the DVDs it's sometimes good to just have distracting noise playing.
Mini toiletries like people take on holiday. They fit nicely into a small washbag so you're not lugging everything with you.
Antibacterial gel. Some people take antibacterial wipes too.
Yes to eyemask. I don't like them but the painkillers made me so dopey I just wanted to sleep in the evenings and the ward lights were still on til 10 or 11.
Snacks and treats to tempt you after the surgery.
I can't think of anything else. Loads and heaps of luck OP! I'll be thinking of you.