My 8.5 month old ds has a lump on the back of his neck where the skull meets the neck. It's quite big, doesn't seem to bother him when I touch it. I've noticed he's been sweating a lot lately, when the rest of him doesn't seem hot. He is grumpier than normal but I put that down to teething.
I thought I'd ask for advice here before I go running off to the GP who might think I'm being silly for bringing him in if its just a virus!