If you have not had any fills, then it is almost impossible that your pouch has streched. This is more likely to occur after you have had several fills and the band is tighter around your stomach creating a small pouch. Until you get fills, there really isn't even a pouch.
From personal experience, there are many times I've wondered if something had gone wrong, only for things to go back to what I considered "normal" a day or so later. The band is very sensitive, and can vary from one day to the next for many reasons other than an issue with the pouch or band itself.