How bad is a craniotomy?

I've got a parietal meningioma that started to grow some and may be causing my symptoms, so it has to come out this week. Then I have to be in ICU for a few days.
I've been falling a lot, dizzy, some vertigo and nausea, bad tinnitus, headaches, trouble sleeping, and frequent tachycardia.
I'm hoping at least some of my symptoms will go away. But I'm not looking forward to 30% chance of seizures afterward.
My only question is how bad is the pain after craniotomy. I don't get any relief from opioids, except dilaudid, which doesn't have to be metabolized. It's a family thing, mom and son the same. My pain doc has for years had me trying everything, including THC, which is metabolized similar to opioids. To make things even more fun I don't tolerate sulfites, which are in a lot of local anesthetics and other drugs. I've made quite a list for my doctors.