does my dogs incision look infected??

He’s almost 2, he was neutered about a month and a half ago, a week after we had him back at the vet because we noticed a little pus, & he had a rash so they gave him a steroid shot & sent me home with antibiotics which I gave them all to him as i should’ve, he’s had a little sore at the top and bottom where the incision was and it looks like a pus bubble. 🤔 do I need to make another vet appt or should I do something?