Welcome to the "Wrapped Club"! You need to keep in mind that the inflammation in your esophagus won't disappear just because you've had the Nissen surgery. It'll take time for that tissue to heal. You said your surgeon told you that it was very, very inflamed. My experience an inflamed stomach and/or esophagus take a long time to heal. I had asthma problems that led me to surgery. My lungs were inflamed after years of being irritated by the refluxing acid. They took several months to heal, and at around 3 months they cleared up, and my breathing was great.
I had "reflux" sensations in the early stages of recovery (I had the surgery on Feb. 27th of this year), and discussed this with my surgeon. He said in the early stages of healing anything is possible. The wrap is swollen, and some acid could possibly slip by. "Pretty much anything is possible at this point" was his response. It has been my experience that whenever my wrap is irritated and bothering me, that's when I get those very infrequent "reflux" sensations. I've read that the esophagus is a "dumb organ" and interprets any pain as reflux. So, are we having reflux? I can't tell you for sure. I can just tell you that my lungs have continued to improve, and I'm breathing freely without any coughing or mucous. That's my indication that whatever I'm experiencing is not true reflux.
I can totally understand your concern, but I think you can rest assured that you're not refluxing. You've got everything going for you. You're young, thin, active, and healthy. Those are four things (in addition to a skilled and experienced surgeon) that set you up for a successful surgical result. Don't waste your time worrying! I think you can be very confident that the burning is residual, from the inflammation that you had at the time of the surgery. Be patient, take care to follow your surgeon's directions regarding diet, and trust that your wrap is just fine.
I hope you'll stay around this forum and report on your recovery experience.
There are lots of people out there searching for information and encouragement as they decide whether or not to move forward with surgery.
It's not a perfect surgery, but it can be a lifesaver for people suffering from severe reflux.
I wish I'd had the surgery years ago, before the steroids I took caused permanent damage to my body. Oh well...better late than never!
Take care, lstek!