Spiney is right. I had a laminectomy/diskectomy without fusion, and I couldn't go back to work even PART TIME for 4 months, and it was 6 months before I could go back full time!!!
I was an optician and on my feet all day.
Be sure you talk to your doctor about POST-OP MEDICATION because you're going to need it. I was in loads of pain afterwards. And it didn't last just a day or two, like the doctor said. It lasted weeks! But of course my surgery was a failure, so I shouldn't even mention it. LOL But you WILL need medication post-op. So ask your doc about it.
And Spiney IS right about the fact that you're going to have to be a "guest" at the birthday party. There isn't much you're going to be able to do at the party. You're just not going to be up to it. Your surgery is a nasty one, and it will wipe you out for quite awhile. Make SURE when you sleep, that you sleep with pillows under your knees. You probably already do, but make sure you do it after surgery. There are "wedges" you can buy for this purpose too. Spiney mentioned vacuuming & mopping -- my doc told me I was never to do that again -- ever!! He said that spinal patients should never do these chores as the back & forth motion is terrible for spinal patients!
Also make sure you don't do any twisting.
I think Spiney covered just about everything. if you're in doubt if you're supposed to do something, DON'T DO IT. You don't want to jeopardize your fusion. Just be very careful, don't do things that could make you fall, and take good care of yourself -- and get proper rest! God bless & let us know how the surgery went, will you please? We'd like to know. Hugs, Lee