Same here. Used to go through coffee like it was water, now I barely finish one cup. It's wild how much the medication changes your relationship with everything, including caffeine.
Had something similar with another supplier once - label just had numbers and a barcode, no info on what was actually in it. Guy said it was legit but couldn't prove it. I didn't want to fight so I took the loss and never ordered from them again.
Heavy burping here too zero appetite. A teacup size was my max before the stomach under my ribs got sore. Hydrate plenty and expect dry mouth. Nausea means ate too much so figure your portion limit. Sleep more is also typical.