I'm 22 years old and I've recently noticed a lump that is about 1 cm in diameter under my chin, back towards the neck. It seems to be round. I first noticed it because my neck felt tender and the ear on that same side ached slightly. You can't notice it by looking. To feel the lump you have to push up under the chin near the neck, and then it pops out. I'm able to move the lump to my jawline. It's very, very mobile. I've had swollen lymph nodes before but never anything like this. It is not painful just tender and slightly uncomfortable. I also have a canker sore in my mouth on the same side as it, I don't know if this could be related but felt I should mention it anyways. Normally, something like this would not bother me so much, but my father was diagnosed with lymphoma about five months ago so it has me concerned. He had a lump on his neck and that is how he discovered it.