Hey,I have had a sore foot for a couple of years now and I notice a swollen spot on the top of my left foot I would not say a bump or a knot it s sore to the touch and it will not allow me to bend my foot all the way down like I usually can,and it hurts pretty bad to walk on it ,it will come and go,what in the world is this?it is right below the bend of my foot,on the top.