my 12 year old dog had his spleen removed

my dog is 12 years old and he had his spleen removed six months ago.He is very tired not eating much and  has formed a lump on his leg. Im not sure what is wrong with him maybe parasites. from the removal of his spleen. what should i do?

[justinem1983]

Hello my dog is 12 years old. six months ago he had his spleen removed.A week ago he became very immoblized. His left leg has a large lump on his inner thigh he cannot pass stool  he seems confused.