Poorly pussy

Today I noticed our cat cobweb had a crusty chin , she would not let me tickle her under the chin . rang the vets and took her there this afternoon we held her down and shaved her chin which has a big puss filled lump on it .
She had an injection and we have to go back in a week the vet thinks it will clear up fine now . Ten minutes at the vet and I am fifty nine pounds lighter but you have to take them.