I have a vein going down from my left ear which seems to be swollen. the vein stops about halfway down my neck, and this is sensitive to touch. help?

Tendon?: It may be just a sore tendon, which is an attachment from one of the neck muscles to the bone by the ear. It isn't very likely to be a vein issue in your age or based on the location. If it is really tender right at the bony area slightly behind and below the ear, that makes it likely to be a tendon. You can try Ibuprofen for a few days and see if it goes away.