I noticed a large lump on my daughters neck 3 weeks ago but it looked about the size of a knuckle, it's now the size of a golf ball and painful. She does not seem sick in any way but this lump is huge when she leans her head to one side. I'm positive it's a lymph node as I have noticeable nodes in my neck in same spot that are painful but the size of a fingernail. Hers is huge and I'm quite worried. Is this common? She's 10