Im not sure if ill explain this very well, but i have a small lump about an inch below my knee, on the inside of my leg. Its smaller than a pea but I can feel it, and almost every day it will become very painful (particularly during exercise). It is also so painful I cant even touch it, brushing it with my hand is just as bad! Ive always not really bothered with it but recently had a steroid injection to treat psoas tendonitis and ive no idea why but it seems worse. It doesnt hurt now as I sit here and write this, but all I have to do is apply a little pressure and its almost unbearable! Does anyone have any idea what it could be? Its almost like a cluster of nerve endings, its that painful.