Hello Dr., I woke up two days ago with a swelling at the bottom of my skull, on the left side, sort of where the base of the skull normally protrudes slightly. It's tender to the touch, and also painful down to the shoulder on that side of my neck. It gives me a headache. I don't have any other symptoms except for what I think might be a cold sore on the left side of my head, above my ear. And another cold sore on my chin. I recently had a chest infection but took a course of antibiotics for seven days, which cleared it. If you could please provide me with any advice, I would greatly appreciate it, as I'm becoming concerned. Thank you, Tim