Chronic Sore Throat

Hi All, 

Just after a bit of advice, I've had a sore throat (especially when swallowing) for nearly 4 months now. Been to the docs numerous times, had 2 complete full blood tests (for all sorts), ultra sound of the throat/glands and also seen an ENT specialist who put a camera down my throat. All of which came back fine... But still the pain is there. Good old aniexty is 0telling me it still must be something serious although with all the tests which have been done i should be confident there isn't.

So question is, has any one had a viral infection which wouldn't shift/go away. Or could the anxiety just be causing this all along? 

Many thanks all in advance