Was it the belt buckle that rubbed <span style = 'background-color: #dae8f4'>on</span>
? Often the metals can cause skin
, Urticaria as Smilerdeb mention
ed, Nickel allergy is very common
, also. If the belt was leather, there are tannins in the processing that can cause a welt. If it was a plastic based on
e, then again, it can cause welts.
The fact your knees are so sore
, makes me think you need to
get some anti-bodies blood tests don
e. The way thyroid anti-bodies affect joints is quite well known.