DS1 has suddenly acquired an enormous, egg sized lump on his neck, just under the jaw line on the left.

No apparent fall or crash or bump, no sign of bite, no fever, no difference in behaviour, breathing, eating, drinking, weeing, pooing, requesting of Mike the Night or anything.

Completely bizzare, and rather sudden.

The lump is painful, and a little red. Possibly a little bruising, but can't be sure.

He is immunised (so shouldn't be mumps).

We're waiting for the Dr, but I'm trying to stop myself from Dr Googling too much

Any ideas? Any experience?