Yesterday, I discovered an unusual lump on the left underside of the shaft of my penis. The lump is roughly half a centremeter in diameter, is clearly a solid/spongy mass beneath the skin, is rather tender when touched, and has developed a small dark spot in the centre (though this could be a result from iritation caused by masterbation). I am worried as to what it is and whether it is dangerous to my health. After browsing several mens health websites, I have found that most of these symptoms allude to a sebaceous cyst, sperm balls, or similar, all of which state that no medical attention is necessary. I am 18, and would be uncomfortable with raising the issue with parents or siblings, but I would, though ONLY if necessary.
Advice?

Go to a doctor. (:

Chances are that if you do talk to family about it, they won't know what to say anyway short of telling you to go to a doctor. Most non-medical people would have the same feelings as you do, and not be comfortable discussing it... nor would they have additiional knowledge about it...

It is always best to be concerned about anything you feel is abnormal, but that does not mean that there is a problem. By going to a doctor you will know for sure. There may be many other explanations for the symptoms that would not need further treatment.

Thanks for the advice!
I don't really think I need to see a doctor anymore.
The lump has pretty much disappeared (after a few incidents involving puss and watnot) and another of my friends said he experienced a remarkably similar event a while ago and it turned out to be nothing serious; just a cyst.

Odd, isn't it, that teenagers are more open about these issues with their friends than with their family!
Or is it just me?
Lol