I am 27 years old, I used to masturbate twice/trice a week depending on the situation. sometimes i felt a niddle like pain on top of my penis right after masturbation but it would go away after a few minutes.recently I am feeling a sudden niddle pinching like pain on the skin my penis, its at the below-middle part where the vein can be seen, going to the tip in between the soft muscle of the top end( i have to see the spot twisting my penis). there is a small lump , for almost 3/4 years but it was painless. I don't know what's the problem but i started to feel it after a whole night long loose bowel movement, i was tired and slept in the morning and when i woke up i figured out this pain i dunno if there is a connection in between, just added up. i was waiting thinking this pain would go away but its been 3days and the pain still is there. i dont feel any burn when i urinate. the pain only is felt when i or my cloth touch it. I am afraid and haven't done anythiing other than urinating, recently i masturbated more than i used to if this pain is for that please tell me what to do, i will stop masturbating forever but don't want to find me impotent :'(