Hiya, I've had a lump behind my left ear for a about 3-4 weeks now.. It's small & hard & it isn't sore or tender at all.. I had a cold about 3 weeks ago so I presumed it was something to do with that, & my Dr. said it was when I went to see him, however, my cold has been & gone & all that's left is a sore throat.. But it isn't sore all the time, just at night when I'm sleeping?