Symptoms of lymphoma?

I think it would be almost impossible for you to stage yourself. Lymph node involvement is commonly internal(chest cavity and abdomenal cavity)and generally reaquires CT scanning to be accurate and possibly biopsies. It is possible to be stage 3 (lymph node involvement on both sides of the diaphragm) and stage 4(involvement of an extralymphatic organ such as the liver, bone marrow or lung) and not to be aware of it. The initial symptoms are nonspecific as you are currently experiencing, which might well be due to anemia. Time and delay is your enemy. Peace of mind might well be worth the investment in a wasted trip to the doctor.