I will start by saying that at 6 months I was pretty much 100% normal, although I still had occasional dumping issues when I ate certain things. That continued throughout my first year, although it became even less frequent. I figured I'd be dealing with that issue forever, but somewhere into the second year I suddenly realized that it wasn't happening any more.
At 2 months, I think your food choice is unwise. First, lettuce and raw veggies are hard on the wrap at this point, and I'd wait a bit for those.
Also, untoasted bread and sandwiches can cause problems. Bread doesn't chew to a liquid...it kind of clumps up, and can get stuck, causing pain and spasms at the wrap site.
When you get pain, it means that whatever you're eating is getting stuck or at least having trouble going through the wrap.
Even though you're two months along, you still need to take small bites and chew, chew, chew, until whatever you are eating turns into a smooth puree that is easily swallowed. Toasted bread can do this, but regular bread and sub rolls can get very clumpy and can get stuck.
If you want less pain...take smaller bites and chew a lot more. Don't eat anything that can't be chewed to a smooth/liquid consistency.
Give your wrap a break...it's still new and healing.
I will tell you this: Although I'm eating everything and feel like I'm back to normal, I still eat a lot more slowly, and chew my food COMPLETELY. Those of us who are wrapped will always need to do this. It's well worth the effort, though! A big plus is that it allows us to fully enjoy the food we're eating, and makes it less likely that we'll jump up for seconds, so it helps us eat less.
If you want to gain weight, lettuce isn't going to help much. Try cream soups and milkshakes. Really, you don't have to worry, because eventually you'll gain back what you're lost. Your weight loss is a result of your recovery, and you'll be eating more once you have healed. I gained all my weight back without any problem, unfortunately!