Penis Pain? Get Lube!
"So before you schedule a doctor's appointment, ask yourself: Did I not use enough lube? Did my penis get caught in my zipper? Have I been masturbating or having vigorous unlubricated sex at too high a frequency? If the answer is yes, then you might find this small site helpful."
Wise - if somewhat alarming - words there from the Penis Pain blog.
Best get yourself some lube then - we've got gallons of the best lubes for every sexual occasion!