is this a sebaceous cyst?

hi im new here.... im not sure if this lump behind my ears is really sebaceous cyst..i was just browsing the net and found an article abt it. its movable and tender..this is the 3rd day.its a bit stingy when i run a finger onto it,otherwise its not.but i find it irritating to look out and its freakin' me out everytime i look at it. i havent told my mom abt it hoping there will be no cause of alarm.i just need help.does putting a hot towel onto it for a few minutes will make it shrink in size? it seems as if its getting a little bigger compared to the 2nd day. if this is really sebaceous cyst, i knw it would eventually go away but is there really nothing i can do abt it w/o consulting to a doctor and get the sebaceous cyst removed? pls help.thanks a lot. :-(