I have a small hard lymph node behind my ear. i was referred for an ultrasound and he said it looked benign but its now feels slightly bigger?

Lump behind ear: Did you have a complete physical exam and work up to figure out why do you have that lump? Is it a lymph node or a lump of fat or a cyst? The ultrasound should give you a good idea if the lump is cancerous or not. However, it is not 100%. If you feel it is getting bigger, then go back and talk to your doctor about this. Ask him about a biopsy, which should give you a more definite answer.