A month ago my cat started scratching his chin so bad that he has an open wound. It started spreading to his ears and eyes so I took him to the vet. They said he was most likely grown allergic to the food I was feeding him and has a bacteria infection. They gave him shots of steroids and medication which I gave him but only the ears and eyes cleared up.
Even though I have changed his food his chin has gotten worse. Now his left ear seems swollen, red and has nasty brown discharge, this is different this how his ears were the first time. It is obvious he is in pain when I touch it but I cannot afford to go back to the vet. Any advice?

