I have a bump on the back of my wrist and behind my ear. should i be worried?

Bumps: A common cause of a bump on the back of the wrist is a ganglion cyst. A lump behind the ear is often an enlarged lymph node which could be from an old infection. A physician would have to examine both these bumps in order to make a diagnosis and advise you. You may be referred to a specialist after the assessment depending upon the findings.