Have enlarged irritating lymph nodes in neck for 4 weeks. Cbc normal. C reactive protein normal. Have night sweats, joint pain &hair loss. Any ideas?

Lymphadenopathy. This could be one or more of a dozen things, including ebv mononucleosis or several mononucleosis-like illnesses such as toxoplasmosis, CMV infection, tuberculosis, to say nothing of the potential for malignancies, although less likely. Other non-infectious entities may include sarcoid, autoimmune diseases, and so on and so on. This must be evaluated by an astute clinician. See your pcp.
See ENT. Hi there, its definitely a good sign that your CBC is normal. Have the night sweats, hair loss, and and joint pain timing coincided with the enlarged lymph nodes? A physical exam is in order since the texture of the nodes is important. If this persists, it might be worth repeating some lab work as well as an ultrasound or MRI of the area could be helpful. Wish you the best.