old jeans fitting tighter

but i still wear the same shirt size, so i know i'm not just getting fat lol. pants feel tighter mostly around the waist and butt areas. i've been on HRT for 3.5 months and these pants never fit as snug. could fat already be starting to get placed there? :0 i know, i'm still pretty early in my transition and can't really visually notice much but omg these old jeans made me realize it's working :'D that same day i was in bed and noticed how my thighs are a little fatter lmao. my legs have always been a little big for a "male" by default anyways but omg... so exciting. :3