I feel your pain. I wasn't "that big to begin with" either, and I had the stall almost immediately. I saw something posted on a FB group that helped me figure it out. So you have fat cells and when you empty them out of fat they fill with Water to hold the fat cell in case more fat comes. When the fat doesn't come it releases the water and goes a away.
I agree that staying off the scale is easier said than done but at least for a few days you've got to.
And if nothing else get your Protein in and your water. It helps. To keep track of your protein you can download the app Baritastic. It's hard to figure out at first but it helps.
Sent from my 2PS64 using the BariatricPal App