Vial Differences?

So i used Ro to get some vials before my Rx got figured out. The vials I got all were labeled zepbound....the first one I had mild side effects (heartburn, nothing bad) in the first few hours. 1 week had me down about 10lbs (mostly water) and some hunger suppression. Weirdly the next vial, I felt no side effects and no hunger suppression and lost about 2.5lbs. now I just did my first injector, within a few hours, I had heartburn and solid appetite suppression, 1 protein shake after a 5mi run and I dont want to eat anything....I just burned about 1k calories, I should be commuting acts of violence on my refrigerator (I will force myself to eat something). Its extremely anecdotal, and hormones do fluctuate.... but I do find it strange.