On The Left Side Of My Jaw, I Can Feel

On the left side of my jaw, I can feel a swollen vein/nerve or something. It's around where wisdom teeth are supposed to come in, but it's on the outside just under the skin. If I rub/prod it gently with my finger I can feel it slide a bit. And feeling under my jaw, there is a lump. This lump pops out when I press my chin down to my chest. They both slide around and hurt quite a bit. I cant feel the vein/nerve or the lump on the other side.