I have had this weird bump at the back of my neck near my hairline. I have had it for about three days now, and it has gotten bigger. It is red and tender to the touch and very hard. Its about the size of a pea. When I touch it I can feel that it is under the skin as well. Please note I have been sick the last 2 days, but Im not sure if that is the cause of it. Also I never shave back there because I am a girl.