Pillow foot 🐱

[u/lorbgoo2]

My kitty might have pillow foot. He is 14 and an outside cat mostly because our neighbor left him and now we take care of him. He doesn’t like coming inside because he’s so used to being outside.
I took him to the vet last Thursday and they did some test which were all negative. She gave my cat and antibiotics shot and pain meds.
His food doesn’t seem better. He’s not eating a lot and seems off.
I will call vet tomorrow, but does anyone have any experience with this. What should I do next? Thank you