Small pimple like bumps on my legs?

I'm a white male, 26. A couple of months ago I began to get a lot of little pimple-like bumps on my knees, thighs and buttocks and occasionally as low as my ankles. (I have never gotten any on my genitals). The bumps itch sometimes but not too much and don't get sore. I have been tested for genital herpes since getting the bumps and came back negative. Any ideas on what it could be????Small pimple like bumps on my legs?
My son has those too, or at least from what Im reading anyways. His doctor said its the same kind of thing as a wort except not permanent. I just have to rub a topical cream on the areas. As unconformable as it may seem, talk to your doctor. Or at the very least try some clean lotion and body wash ( no perfumes or dies like Aveeno) and change your laundry stuff..could be a form of a rash from dry skin or an allergic reaction.