They don't accept walk ins, you will need an appointment in order for your cat to be seen by the vet.
Your cat is still young but it sounds like tumours. Take him in. Try and call ahead. You should have taken him as soon as you saw the first ball since things get worse over time. Please understand that he may need to be put down. A vet will encourage you to keep the animal alive just to take your money. The ASPCA will be honest and tell you if your animal should be put down. Its hard but its better not to let them suffer.
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