I have had this hard lump on my lower left side of my back close to my spine for several months now.  It doesn't move or hurt to the touch only when i put pressure on it will i start to feel get this uncomfortable dull feeling.  there are days where i won't even notice it but then there are days where its very uncomfortable for me especially if i lay or sit a certain wait. There are days where it feels smaller than usual then there are days where its bigger than usual i need some advice on what to do about it and wether i should mention it to my doctor