Have you been icing the soreness at all?

Yes, try an ice pack and Advil or Aleve if you can take it (NSAID)(Sorry don't know how much 16 0r 13 stone is, from Washington State) It does sound like inflammation. If you don't get the swelling down, it will get worse, trust me I have severe Bursitis and Tendonitis and had to have Cortisone shots in 4 joints and you don't want that good luck and let me know how it goes.