Swelling On The Adam's Apple. Pain While Swallowing. No Cold. Causes?

Hi. I ve had swelling to the front of my throat/adam s apple on and off over the past 4/5 weeks, it comes on very swollen for about a week or so, goes down a bit then comes back up swollen again. During this it gets sore and hard to swallow . I don t really have any symptoms of a cold but I do feel physically run down and tired. I m 32, fit and health, don t smoke and don t drink much (maybe 5/10 units per month). No history of major illness and rarely get sick.