Hi!

 I have had a hard lump at the back of my skull by the muscle for about 2 to 3 years.

 It does not grow and has always remained the same size.

 This is not in the middle but on the right side along the connection of the spine, this bump is not palpable when I turn my head to the right, but it can be felt when I turn my head to the left and when I'm yawning it will get harder and easier to feel.

 This is a hard bump, which I don't feel can move.  It will be about the size of a small marble.  Of course if I google the symptoms I immediately arrive at a bone/brain tumor.  Of course this worries me quite a bit and this is also a big reason why I haven't gone to the doctor yet.

 I tried to massage him last night (maybe a muscle contraction but it normally doesn't last long) and now it has become sensitive.

 I also occasionally suffer from sudden headaches in my eyes and occasional stings during sleep, these last 2 to 3 seconds and are gone again.  I have never linked these together because I also have a lot of stress in my life and experience a lot of fear that something is wrong with my body.

 I understand that I have to go to the doctor for this but is it common that you have a tumor at the back of the skull or a swollen lymph node etc?