Red patch of skin on penis tip

While on vacation last week at the beach, I noticed a red patch of skin on the tip of my penis.  The area is very small, but noticeable.  The patch is flush with the skin.  What I mean by this is it is not a raised patch of skin.  It's not painful.  It doesn't hurt when I pee.  It is not filled with any puss/liquid of any kind.  Literally, it's just a red patch of skin located right next to my urethra.  It looks and feels like dry skin, and develops a thin layer of what I would call dead skin over top of it.  However, seeing as how this has never happened before I am not fully convinced it is just dry skin.  This morning while "inspecting", I noticed the same exact thing has developed on my foreskin. I'm kind of freaking out here.  

I've only ever had sex with one person, who was tested last month for STD's and is completely clean.  I'm a pretty clean person and I take decent care of myself hygiene wise.  

Has anyone ever had a similar experience?  Does anyone have some insight?  Anything would be appreciated.  Thanks.

[joggen]

Doesn't sound like an STD. Could be any number of non-STD skin processes (infection, allergy, irritation). See your dermatologist.