Welcome to Healing Well! Ten weeks is much to soon to be making any decisions as to the success or failure of a Nissen surgery. The healing is a long-term thing, and it takes a full 6 months for most of the healing, and a full year for the rest.
I also had the surgery due to breathing issues, but I believe they were different than yours. I have asthma, and the reflux I was experiencing caused it to be uncontrollable.
It took me almost exactly 10 weeks to begin seeing improvement. At that point I finally was able to go off my nebulizer treatments and was breathing better again. Over the next months and even a year or more, my lungs continued to improve, until today they're healthy and I'm doing fine.
Each person's recovery is unique. Try to relax into it and let it happen at its own pace. It takes time to undo the damage that was done by reflux. You didn't get the problem in 10 weeks, and it's probably not going away in 10 weeks.
Again, welcome to the forum!
I hope you begin to feel relief soon.