Ive been experiencing some weird things these past few month and have been worked up over every little thing i can find wrong with me. Ive had anxiety problems and my heart has been pounding out of my chest. But just recently I noticed a lump (not visible externally but I can feel it) on my mastoid bone behind my hear which i have been concerned about the most. Its not painful to the touch and isnt extremely soft nor really hard but is distinguishable from the bone. I checked my left mastoid and it didnt have this lump like the one on my right mastoid bone. Its only been a couple of days so im not sure if its grown but its really worrying me. Some other possible symptoms ive been having that could be related to this that I am having are anxiety/depersonalization or derealization and headaches which are sometimes sharp and in the back of my head and sometimes full and dull, sometimes light/sound sensitive. Those are a few things off the top of my head that ive been experiencing that I would say are related but im here to find out if they are and to help you help me figure out whats wrong with me. Could this be a tumor or something of that nature? Ive looked up swollen lymph nodes but im not convince that its that. Im 16 so I feel like I shouldnt be having these problems which is really bothering me. Your help is greatly appreciated, thanks