If it appears to be a hard lump either near or, on a vien it is a thrombosed vien. What this means is, there has been a blockage caused by too much pressure being exerted on the vien. It was most likely cause by too much pressure during jelquing or an intense squeezing routine. It should clear up in a matter of days....a week at the longest. You can help it clear up more quickly by massaging it and the surrounding area for a few minutes several times a day. It wont kill you or your penis. How to prevent this in the future? Start your jelqing/squeezing routine with a less intense beginning set of jelqs/squeezes for around 5-10 minutes before getting into the more intense stuff.