Body changes w/o WL

I just took week 7 shot today, and multiple people have told me I look smaller. Funny thing is I've been toggling between the same ~5lbs since I've started. My lifestyle hasn't drastically changed since starting. I was working out and tracking for many months before getting prescribed (which is a main reason I did bc i saw no results).

Has anyone experienced body composition changing noticeably without losing weight? And i know, "muscle gained, fat lost" is totally a thing.