What you're describing isn't "typical". Still, it's possible to get pains post-op, even at month 7 that can mimic reflux. There were times during the first couple years post-op when I'd be awakened by a sharp pain at the wrap site if I slept on my left side. The pain would subside as soon as I changed positions. I'm now 4 years post op, and I can sleep on my side without a problem.
It is still possible to actually get reflux, even after having surgery. It will be much less frequent and less severe, but it can happen if you eat certain offending foods.
Pain at the top of the mouth is new to me. I've never heard of that symptom, but if you had it pre-op, it's not out of the realm of possibilities that it might still bother you from time to time. I think it's the frequency, duration, and severity that are critical in deciding whether or not it is something to be concerned about.
Wish I could be more help!
Nissen Fundoplication 2/09
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”