Hiya Sleeved,
Welcome to the forum !!
I had exactly the same thing which made NO sense cos I'd be starving (that gnawing in the bottom of your stomach) a very short time after having eaten - so I knew it could not be real hunger and it certainly wasn't head hunger.
"Reflux" can present as hunger especially in the early days.
I was already taking Pariet but switched over to Nexium 40mg and the symptoms were gone after about 3 days (yay.)
Have a chat to your Surgeon or GP about a Script (sooner rather than later - cos it's an AWFUL feeling.)
And of course make sure you are keeping your fluids up as dehydration can also mask itself as hunger.
Let us know how you go.
Tara