question: I have a lump on the back of my neck/ bottom of the skull.  It comes and goes, but is not movable and very hard.  It has gone down in the last two days, but I have been quite scatter minded and somewhat light headed.  It has done this a couple of times and the concern is growing.  Any idea what it could be?  I have looked all over the web for answers and only found a lot of people with the same symptoms.  HELP!!