The core question underneath this is really about whether what's going on with you right now counts as normal, and whether the number on the scale will eventually justify pushing through the early rough patch.
At 2.5mg, the commonly reported experience is mild queasiness during the first couple weeks, sometimes tiredness or constipation, usually fading as your system adapts. That starting dose is deliberately conservative, built more around tolerance than fast results. Most people see somewhere between 2 and 5kg the first month, much of that being water and stored glycogen, and the quieting of that mental food chatter tends to be the earliest real sign it's kicking in before the scale even catches up. Anyone here recall their own first month on the entry dose, did the number move right away, or did it take stepping up before anything really happened?