Generally the swelling we talk about in the first two weeks is internal at the wrap site. It makes it increasingly more difficult to swallow. I don't remember excessive swelling that comes on suddenly like that, although it's certainly possible that others here have.
Still, I'd call your doctor's office. There must be somebody on call who could talk to you about what you're experiencing. It's always better to check with your surgeon whenever there's something happening that you don't understand or is bothering you.
Your surgery is still pretty recent, and I'm sure the office is used to getting lots of calls with questions.
You don't want to assume anything. Most likely it's just normal swelling, but I think it's wise to ask. I know that most people (myself included) have to wear "fat pants" for quite a while after the surgery because of bloating, so that part's very normal.
I'm sure it's fine, but if it were me I'd check on what the surgeon thinks.
BTW, I think you'll still lose plenty of weight in the next six months if you want to. This surgery does help with weight loss!
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.”