Had 1 top one out at 22 and the other grew through OK. The bottom two didnt have enough room to grow through so had a tiny bit poking through the gum. Was agony for a few years and they were infected several times so had to have antibiotics. Eventually had them out under general anesthetic in 2004 (age 24). My dentist was convinced they would grow through and didnt want to remove them.

Oh and r.e the swelling, against all medical advice, SQUEEZE IT, I did, feels much better