Could my 8 year old really have cancer?

About 3 weeks ago, my son came to me with a lump on his neck. By the next day it was four. One had grown to one cm. The others pearl size. They did not hurt and were fixed. I noticed he was sweating alot at night and had a fever(low grade)for a few days, then not for a few days. The pediatr. had blood work done and his sedrate was ellevated. He also itches alot, especially at night. We scheduled a biopsy, but had bloodwork again and his sedrate went down. His alp was very high 200 and something. The dr. said in kids this is normal. So, we cancelled the surgery and decided to wait and check blood again in a month. well, that was a week ago and his fevers came back wednesday night. He is still having drenching night sweats and itching.,His stomache is very bloated but she says he is constipated. She is concerned agin because he is still having all this with no apparent reason. No sore throat, ear infection..ect! Could he really have lymphoma when all the blood work said he was fine. I am not trying to freak again and just be patient, but I am worried. We are going to do biopsy now, but I am once again waiting for that appointment. What do you think. Anyone been through this? Are these the symptoms? He has lost 6 pounds in 3 weeks, but eats pretty good, most of the time. thanks