Re: supraclavicular lymph nodes.
The chest xray you had should suffice, as the lymph nodes in chest would have been seen if enlarged. Nodes in the front of neck often stay slightly enlarged in people who have frequent respiratory infections, sore throats, tonsillitis, etc. The only one a bit out of ordinary is the supraclavicular one. I think I would see an internist, get all node areas checked as well as liver and spleen on exam, and see what an internist thinks. Many viruses, like mono, can cause enlarged enlarged lymph nodes, and sometimes the infection is mild enough there are no other symptoms. Autoimmune disorders can cause them too, and an investigation can be done later if the nodes get bigger, don't resolve, or you develop symptoms.