Yesterday I noticed that below my jaw, this smallish lump inside (I mean within the skin)..but under my jaw but it s very tender when I touch it. I have no idea if it has always been there (which I doubt.) It does not appear to be swollen, either. It doesn t hurt when I swallow or anything, but sometimes when I move my head and touch it. And I have no idea if this relates, but two or three days ago, three cold sores appeared on my bottom lip at the same time and this is now the second day of it being swollen.