Itching Penis?

[misterr]

About 30 days ago, I had unprotected sex while in Brazil.  Very soon afterwards, my penis started itching, and over the next few days I felt like I was sweating a lot more in the groin area.  There are no visible signs of any kind of any kind of rash or bumps or anything.  It still itches and there is a very low level of discomfort at times (sort of just like a hightened sensitivity.  I was tested for some of the normal STD's (Chlamydia, Gonorrhea, Syphilis, Herpes Simplex 1&2, Hepatitis B&C, and HIV) and all came back negative.  There is no pain or discomfort when I urinate.  

I am wondering what it could be?  Any suggestions?

[Vance2335]

Best bet is to see a Dr for any diagnosis. I would hate to tell you to use this product or that product and have it not work or make the situation worse.

[misterr]

Thank you for replying so quickly.  I suppose it's good that the symptoms are probably not STD related.  If I try a jock itch spray or something would that cure a Yeast or general fungial infection?  

Is there a test or something I could do to determine if it's fungial, or would I have to go see a Dr to have them diagnose?  Again, I really don't see any rash or bumps or anything.

[Vance2335]

well herpes, syphilis and HIV are not 100% conclusive at the 30 day time frame.
it could be like a yeast infection, irritation or maybe a fungial infection. have never heard of an STD causing those symptoms.