Lymph Nodes

I have had swelling of the lymph nodes for a month now under my chin, below the jawline. On lymph node is bigger than the other. I have not had any infections, no sore throat, allergies, sinuses or colds. The pain is intense at times. The bestway to describe is sharp, burning, stabbing right on the lymph nodes. My ears ache. (deep ache). The back of my head feels like it is on fire. My GP did discover another lymph node behind my right ear that was not there 4 weeks ago. That lymph node is hard and fixed, does not move, but is painful and i can feel the sharp shooting pain radiating from it. The sockets of my eyes hurt as well. The area underneath my chin is also in pain where the lymph nodes hurt. My tongue has a scalded feeling to it everytime i eat. I am being sent to an ENT for this. My other symptoms are weight loss (unintentional); i have lost 25lbs in 4 months. I have frequent urination, my thigh muscles ache, unable to sleep, night sweats (not all the time). Do not run fever. My GP has run so many test on my blood and they have all come back normal. They have done MRI's, CT scans, Ultra sounds, and everything comes back okay. I do not know when my appt. will be, but i was wondering what should I ask this new specialist?  What tests need to done? I have never been to an ENT, so i was wondering if anyone knew what i should expect. Thanks.