Sudden Lump On Back Of Head On Right Side Above

Sudden lump on back of head on right side above hair line behind the ear extremely painful and a tingling feeling on the back of my head to to middle of head on right side and towards the front of head but it stops right above the middle of my ear. Suddenly appeared about 2 weeks ago but not as painful ad suddenly disappeared the next day. All tho happened after a sudden pressure in the same place that was so bad I ended up in the ER.The doctors had no answers for me. I told the ER physician that they just needed to drill a whole there to release the pressure. It was not a migraine like I usually have,this time it was not painful because of pain it was only pressure the lights did not bother me. Any kind of sound did not me. I have a history of head injuries during childhood the first was a nail stuck in my skull on the crown of my head, the second time my head was cracked open by a metal wagon handle on the top of my head towards the front. I also have been having complications with my heart but I am not sure if I is due to my heart murmur or not. My hear problems did not start this bad untill these recent problems with the lump also I cannot focus my eyes for some reason but my vision is not blurry.