Bump in my right armpit.

I recently noticed a bump in my right armpit.  I was thinking that it could be an enlarged lymph node.  I have had what I believe is a common cold and understand that it can cause enlarged lymph nodes, but I would think they would occur on the neck, for instance, instead of under the arm, if it was due to the cold.  There is, however, a mole that appears somewhat suspicious under the same armpit.  Thanks.