I had a kidney stone and ended up in the ER. The pain was insane and they kept giving me morphine and opiates stronger than morphine(dillaton?)

I stayed overnight and was on pain drip which I used sparingly because The drugs were making super nauseous. I couldn't keep down any food that whole day and threw up constantly for 12 hours straight.

I'm 2 days out from this incident and I feel very foggy and more head pressure. I'm worried I have long term damage from these strong drugs. My wife thinks it's anxiety the reason I feel like this but common sense would say these drugs can't be good for the brain. Anxiety does play a role in everything to some degree but not the main factor.

I don't think you did any damage. It can take a while to clear all of the opiate or other pain killer. I get very nauseous from Demerol, even when they include the anti-nausea drug so I would not be concerned.

There are some dietary things you can do to help your body with kidney stones. My wife reduced the size of hers with such a plan. You could google kidney stones and natural remedies.