I had surgery a week past today. I have a number of

Hi,
Congratulations on your successful surgery. I am going to give you a couple general thoughts related to your posts, and indirectly answer your questions (stated and unstated).
You will eventually drive yourself nuts getting on the scale every day. My advice would be to figuratively throw it out the window. Day to day weight changes have nothing to do with food choices but are dictated by changing fluid status. The changes (both good and bad) that you make in the kitchen and gym don't show up on the scale for 1-2 weeks after. Trying to read the tea leaves of daily weight fluctuations can be frustrated and misleading. Be strong and ditch the scale.
Slim fast shakes are kryptonite for Bariatric patients, as they have lots of carbs that slide right past the band. I always want my patients to stay away from milk, juice, soda and any kind of smoothie, as they defeat purpose of the band. The Nutribullet is the devil's kitchen instrument. Protein shakes are an exception (when made with water, not milk!!).
Everyone has low energy at your stage after surgery, mostly due to being on liquids for 2-3 wks. If your liquids are going down fine, move on to a blended or purée diet. There is something magical about blended whole wheat spaghetti and lean turkey meatballs (hot) at your stage after surgery. Your energy will improve quickly once you get better nutrition. You need protein and complex carbs; slim fast isn't the right answer now (or ever, fwiw).
You have had a lot of things in and around your body these past two weeks, some of which can cause an allergic reaction. I don't have a good answer but the likely player is always the pain medication. I have never seen an allergic reaction to the band itself.
If I missed something, let me know. The important thing to consider is that you are where all bandsters are at your stage. Don't stress about weight, and move on to frequent, small nutritious meals. High protein, high veggie, low carb.
Good luck,
Dr Dan