You are still recovering from surgery so your weight will likely fluctuate for a few weeks (although overall should be going down). I think as we start using up the glucose in our fat cells it can cause some fluid retention which causes our weight to go up temporarily. Don't weigh yourself everyday - it's the fastest way to de-motivate yourself if you don't see any movement, or only upwards movement. I "gained" five pounds after surgery but have been slowly losing since then. It's best to pick one day a week for an "official" weigh in (for me it's Monday morning) - don't worry what's happening the other days (easier said than done!).
Stick to your post-op diet, walk as much as you can, and distract yourself by doing other things. Make a list of non-scale victories (NSV) that you can track or look forward to, like fitting into smaller clothes, being able to sit on a bus/subway seat with enough room for another person to sit beside you (and not touch them!), seeing your collarbones again, being able to fit into smaller/former shoe sizes since your feet may have been too big/swollen from years of being overweight (this was a big one for me), being able to wear heels again without being in pain, not needing a seatbelt extender when flying, etc, etc. You can also make a list of "rewards" or future plans to look forward to. Like, when you lose your first 10 or 20 pounds. 50 pounds. 100 pounds. Making it to "onederland" (under 200 pounds). For example, for me, once I hit goal weight (or near it), I'd really like to do a physical challenge that I really couldn't do before because of my weight (and therefore my knee and back problems). So climbing Kilimanjaro and walking the Camino de Santiago in Spain are two bucket list items that I would like to do once I lose the weight (and save the money) to do so. Having a really great makeover (hair, makeup, clothes, everything) is something else I'd like to do.
Another thing to remember is that (I think, for all of us), we didn't gain weight every single day as we were overeating or making poor food choices throughout our lives, it was a gradual, but steady, increase over time. Same with losing weight. It's not going to happen every day in a steady decline. Some days (or weeks! It will happen eventually) the weight may not move at all, or may go up a little. But stick to the plan, try not to fall off the wagon no matter how tempting, and the weight loss will be steady over time. Not every day, but it's happening.