Did I get a bad batch?

Been taking 5mg for a year and dropped 80lbs so I never titrated up. This last box I have taken 3 different weekly injections and have noticed that my appetite is back with a vengeance. In fact, I am still hungry even after eating! It's almost as if the medication isn't there or has lost its potency. Is it possible that I got a bad batch or that I have become adjusted to 5mg?