8 year old son looks constantly tired and pale, have noticed his energy levels has decreased over last few weeks and he has become quite irritable and generally not himself. he also complains of having a sore throat and pains in his sides and legs. he is eating ok and and drinking fluids ok the only other thing ive picked up on is that his nose is constantly congested and his breath has a foul odour. Gp has done bloods but fbc and glucose result marked as satisfactory? he also has a few enlarged lymph nodes which has been like this for a few weeks?