i have a hard, small knot on the bone behind my ear, and that lymph node is also slightly swollen, it does not hurt, but i am worried. i am 27 years old and never really have any health problems, i weigh 140 pounds and i am a bit of a hypochondriac. I was bitten about 6 times by black flies two days aGO and wonder if that hard lump on the bone behind my ear might also be a gland that has swollen as an immune response?? i am scared about this knot, can you help me?