I've got a cat here with a sore paw, initially discovered after bloody footprints on the bedclothes. It took a few days to discover which cat it was but when I noticed smaller cat licking it's paw and his brother licking him I tried to look. It looks a bit swollen and tonight there are more pus/bloody marks on Ds2's bed. Do these things heal by themselves or is this a vet's trip? He seems fine in himself but they are new cats, and we are new to cat owning, and I don't know when to call it for the vet!