What Causes A Knotted Area On My Skin Oozing Pus?

i think i may have a worm of some sort under my skin, i have a small area which is like the skin is knotted up and every so often i end up squeezing puss out of it, this morning the skin had broken completely leaving a little puncture wound, and under it i can see something white which looks different to the rest of the area, do you think this could be a worm and if so how do i remove it?